( e)-5-alkoxy-1-phenylpentan-1-one o-(2-( n, n- disubstituted amino)ethyl) oximes and their therapeutic use for covid-19 disease

Abstract

The present invention relates to (E)-5-alkoxy-1- phenylpentan-1-one O-(2-(N,N- disubstitutedamino)ethyl) oximes and the methods of preparation thereof. The present invention describes the (E)-5-alkoxy-1-phenylpentan-1-one O-(2-(N,N- disubstitutedamino)ethyl) oximes as potent anti-COVID-19 agent.

Description

[0001] PT / 2025 / 17225

[0002] (E)-5-ALK0XY-1-PHENYLPENTAN-1-0NE 0-(2-(AZ, N- DISUBSTITUTED AMINO)ETHYL) OXIMES AND THEIR THERAPEUTIC USE FOR COVID-19 DISEASE

[0003] FIELD OF THE INVENTION

[0004] The present invention relates to the (E)-5-alkoxy-1 -phenyl pentan-1 -one O-(2-( / V, / V- disubstituted amino)ethyl) oximes and the method of preparation thereof. The present invention particularly relates to the (E)-5-alkoxy-1 -phenylpentan-1 -one O-(2-( / V, / V- disubstituted amino)ethyl) oximes for its therapeutic application in treating COVID-19.

[0005] BACKGROUND OF THE INVENTION

[0006] Fluvoxamine (FLV), is a selective serotonin reuptake inhibitor (SSRI), widely prescribed for the treatment of major depressive disorders (MDD), obsessive- compulsive disorders (OCD), and various anxiety disorders such as panic disorder and post-traumatic stress disorder (PTSD). The controlled release (CR) form of FLV is approved for the treatment of social anxiety disorder. FLV, which enhances serotonin levels in the brain, thereby helping to improve mood and reduce anxiety. Known for its tolerability, FLV is a preferred choice for many patients (Neuropsychiatric disease and treatment 2005, 1, 289-99). Beyond its established uses, FLV has shown promise in COVID-19 treatment. It gained attention due to its promising results in a small, double-blind, placebo-controlled, randomized study suggesting it may prevent the clinical deterioration of patients with mild COVID-19 cases, (J. Clin. Pharmacol. 2022; 88:2065-2073). FLV acts as a sigma-1 receptor agonist, modulating the inflammatory response. Through this mechanism, FLV can control inflammation, crucial in COVID-19 progression, particularly in early stages. These findings imply the potential repurposing of FLV in COVID-19 management, expanding its therapeutic role beyond traditional psychiatric uses (Frontiers in pharmacology 2021 , 12).

[0007] The emergence of new SARS-CoV-2 variants has highlighted challenges in vaccine efficacy and the need for adaptable strategies. These variants introduce new symptoms, including neurological disorders affecting a sizable part of patients who may progress to severe stages, emphasizing the importance of early diagnosis and PT / 2025 / 17225 treatment to mitigate symptoms and manage disease impact.

[0008] In light of these challenges, there has been considerable interest in exploring the therapeutic potential of antidepressant drugs, such as FLV, fluoxetine, escitalopram, paroxetine, and amitriptyline, for treating SARS-CoV-2. These drugs have drawn interest for potential COVID-19 treatment due to their ability to inhibit acid sphingomyelinase (ASM), which mitigates the inflammatory responses and other pathophysiological processes associated with COVID-19. FLV (FLV) has many advantages over the current SARS-CoV-2 drugs related to economy, safety standards, availability, oral administration and prescription for children as well as adolescents. Its trifluoromethyl (TFM) group is a key active moiety found in many drug molecules which is known for high binding affinity, favorable electrostatic and hydrophobic interactions with many biological targets. Hence, exploring FLV-based compounds with TFM modifications could potentially yield prophylactic drugs against COVID-19. Therefore, continued research is essential to fully elucidate the mechanism of drugs and their efficacy against SARS-CoV-2, offering vital therapeutic options amidst the ongoing global health crisis.

[0009] OBJECTIVES OF THE INVENTION

[0010] The main objective of the present invention is to provide (E)-5-alkoxy-1 - phenylpentan- 1 -one O-(2-( / V, / V- di substitutedamino)ethyl) oximes for the inhibition of SARS- CoV-2

[0011] Another objective of the present invention is to provide a process for the synthesis of (E)-5-alkoxy-1 -phenylpentan-1 -one-0-(2-(A / ,A / -di-substitutedamino)ethyl) oximes using cheap and commercially available reagents.

[0012] Another objective of the present invention is to evaluate the synthesized compounds against the COVID-19 virus.

[0013] SUMMARY OF THE INVENTION

[0014] The present invention provides a compound of general formula A or a salt thereof; PT / 2025 / 17225

[0015] Formula A

[0016] J wherein Ri is selected from the group consisting of substituted or unsubstituted: aryl, heteroaryl, aliphatic ketones, cycloalkyl, alkyl, and alkenyl;

[0017] R2 is selected from the group consisting of hydrogen, substituted or unsubstituted alkyl and substituted or unsubstituted aryl or R1 and R2 may together form a substituted or unsubstituted cycloalkyl group; and

[0018] R3 is a haloalkyl.

[0019] In a preferred embodiment of the present invention the substitutent on R1 is selected from the group consisting of alkyl, alkoxy, halo, trifluoroalkyl, alkenyl, thiophenyl and aryl.

[0020] In a preferred embodiment of the present invention the compound of general formula A is selected from the group consisting of:

[0021] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(benzyl(2,2,2- trifluoroethyl)amino)ethyl) oxime; A1

[0022] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((4- methoxybenzyl)(2,2,2- trifluoroethyl)amino)ethyl) oxime; A2

[0023] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((4-bromobenzyl)(2,2,2- trifluoroethyl)amino)ethyl) oxime; A3

[0024] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(((6- bromobenzo[d][1 ,3]dioxol-5-yl)methyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime; A4 (E)- 5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((benzo[d]thiazol-2- ylmethyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime; A5 PT / 2025 / 17225

[0025] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(((5-bromothiophen-2- yl)methyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime; A6

[0026] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(((4-methylthiazol-5- yl)methyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime; A7

[0027] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(((E)-2-phenyl-3-

[0028] (phenylthio)allyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime; A8

[0029] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-

[0030] ((cyclohexylmethyl)(2,2,2- trifluoroethyl)amino)ethyl) oxime; A9

[0031] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(((E)-but-2-en-1 - yl)(2,2,2- trifluoroethyl)amino)ethyl) oxime; A10

[0032] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((2,2,2- trifluoroethyl)(undecyl)amino)ethyl) oxime; A11

[0033] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(isopentyl(2,2,2- trifluoroethyl)amino)ethyl) oxime; A12

[0034] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((4-fluorobenzyl)(2,2,2- trifluoroethyl)amino)ethyl) oxime; A13

[0035] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((2,2,2-trifluoroethyl)(3-

[0036] (trifluoromethyl)benzyl)amino)ethyl)oxime; A14

[0037] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one O-(2-((2,2,2- trifluoroethyl)(4- (trifluoromethyl)benzyl)amino)ethyl) oxime; A15

[0038] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(cyclopentyl(2,2,2- trifluoroethyl)amino)ethyl) oxime; A16

[0039] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(cyclohexyl(2,2,2- trifluoroethyl)amino)ethyl) oxime; A17 and

[0040] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(hexan-2-yl(2,2,2- trifluoroethyl)amino)ethyl) oxime; A18. PT / 2025 / 17225

[0041] The present invention provides a process for the preparation of compounds of formula A, wherein the process comprises: reacting compound (1) with compound (2), wherein R1 is selected from the group consisting of substituted or unsubstituted: aryl, heteroaryl, aliphatic ketones, cycloalkyl, alkyl, and alkenyl; R2 is selected from the group consisting of hydrogen, substituted or unsubstituted alkyl and substituted or unsubstituted aryl or R1 and R2 may together form a substituted or unsubstituted cycloalkyl group and compound (3) wherein R3 is a haloalkyl, in presence of phenylsilane and a solvent at a temperature range of 70 °C to 110 °C for a period of 16 h under the argon atmosphere to obtain the compound of Formula A.

[0042] In an aspect of the present invention the compound (2) in the above mentioned process is an aldehyde selected from the group consisting of benzaldehyde, 4- methoxybenzaldehyde, 4-bromobenzaldehyde, 6-bromobenzo[d][1 ,3]dioxole-5- carbaldehyde, benzo[d]thiazole-2-carbaldehyde, 5-bromothiophene-2-carbaldehyde, 4-methylthiazole-5- carbaldehyde, (E)-2-phenyl-3-(phenylthio)acrylaldehyde, cyclohexane-carbaldehyde, (E)-but-2- enal, undecanal, 3-methylbutanal, 4- fluorobenzaldehyde, 3-(trifluoromethyl)benzaldehyde, 4-

[0043] (trifluoromethyl)benzaldehyde.

[0044] In an aspect of the present invention the compound (2) in the above mentioned process is a ketone selected from the group consisting of cyclopentanone, cyclohexanone and hexan-2-one.

[0045] In an aspect of the present invention the compound (3) in the above mentioned process is trifluoroacetic acid.

[0046] In a preferred embodiment, the solvent used is toluene.

[0047] In a preferred embodiment, the temperature is 70 °C. PT / 2025 / 17225

[0048] In a preferred embodiment, the yeild of compounds of formula A from the above entioned process is 58 to 81%. .

[0049] In a preferred embodiment the solvent used is toluene.

[0050] Candidate drug molecules showing more than 90 % reduction of SARS-CoV2 viral RNA at 0.5 pM were considered to derive the EC50 values. The EC50 values for the selected candidate drugs were calculated by treating the cells with different concentrations (0.025 pM, 0.05 pM, 0.1 pM, 0.2 pM, 0.4 pM, 0.6 pM, 0.8 pM and 1.6 pM) and the experiment was conducted as described below. The Dose-Response curves were generated by plotting Relative Viral RNA (%) against log concentration (nM) of the tested compounds through the Non-linear regression analysis (GraphPad Prism version 8.4.2). The tested candidate molecules, A1, A3, A14, and A15 showed EC50 values of 0.108 pM, 0.091 pM, 0.141 pM, and 0.246 pM respectively.

[0051] LIST OF ABBREVIATIONS

[0052] 1 ) FLV- Fluvoxamine

[0053] 2) SSRI - Selective serotonin reuptake inhibitor

[0054] 3) MDD- Major depressive disorders

[0055] 4) OCD - Obsessive-compulsive disorders

[0056] 5) TLC - Thin Layer Chromatography

[0057] 6) PTSD - Post-traumatic stress disorder

[0058] 7) CR - Controlled release

[0059] 8) COVID-19 - Coronavirus disease of 2019

[0060] 9) ASM - Acid sphingomyelinase

[0061] 10) TFM - T rifluoromethyl

[0062] 11 ) SARS-CoV-2 - Severe acute respiratory syndrome coronavirus 2

[0063] 12) CHCI3- Chloroform

[0064] 13) TFA - T rifluoroacetic acid

[0065] 14) CDC -Deuterated chloroform PT / 2025 / 17225

[0066] 15) TLC- Thin Layer Chromatography

[0067] 16) MHz- Megahertz

[0068] DETAILED DESCRIPTION OF THE INVENTION

[0069] For a better understanding of the invention, a detailed description of the invention along with detailed description of the preferred embodiments of the present invention is explained below with reference to the accompanying tables and drawings.

[0070] For better understanding the present disclosure, certain terms and definitions should be read in the light of the remainder of the disclosure and understood as by a person of skill in the art. The terms used herein have the meanings recognized and known to those of skill in the art.

[0071] Ratios, concentrations, amounts, and other numerical data may be presented herein in a range format. It is to be understood that such range format is used merely for convenience and brevity and should be interpreted flexibly to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited.

[0072] Those skilled in the art will be aware that the present disclosure is subject to variations and modifications other than those specifically described. It is to be understood that the present disclosure includes all such variations and modifications. The disclosure also includes all such steps, features, compositions and compounds referred to or indicated in this specification, individually or collectively and any and all combinations of any or more of such steps or features.

[0073] The main aspect of the present invention is to provide a compound of Formula A, or a salt thereof; PT / 2025 / 17225

[0074] Formula A J wherein R1 is selected from the group consisting of substituted or unsubstituted: aryl, heteroaryl, aliphatic ketones, cycloalkyl, alkyl, and alkenyl;

[0075] R2 is selected from the group consisting of hydrogen, substituted or unsubstituted alkyl and substituted or unsubstituted aryl or Ri and R2 may together form a substituted or unsubstituted cycloalkyl group; and

[0076] R3 is a haloalkyl.

[0077] The substitutent on R1 in the compound of Formula A is selected from the group consisting of alkyl, alkoxy, halo, trifluoroalkyl, alkenyl, thiophenyl and aryl. The present invention provides a process for the preparation of compounds of formula A, wherein the process comprises reacting compound (1 ) with compound (2), wherein R1 is selected from the group consisting of substituted or unsubstituted: aryl, heteroaryl, aliphatic ketones, cycloalkyl, alkyl, and alkenyl; R2 is selected from the group consisting of hydrogen, substituted or unsubstituted alkyl and substituted or unsubstituted aryl or R1 and R2 may together form a substituted or unsubstituted cycloalkyl group and compound (3) wherein R3 is a haloalkyl, in presence of phenylsilane and a solvent at a temperature range of 70 °C to 1 10 °C for a period of 16 h under the argon atmosphere to obtain the compound of Formula A PT / 2025 / 17225

[0078] In an embodiment, the present invention provides a process for the preparation of compounds of formula A (Scheme I), wherein compound (2) is an aldehyde, comprising: reacting FLV (1 ) with reactant aldehyde (2) selected from benzaldehyde, 4- methoxybenzaldehyde, 4-bromobenzaldehyde, 6-bromobenzo[d][1 ,3]dioxole-5- carbaldehyde, benzo[d]thiazole-2-carbaldehyde, 5-bromothiophene-2-carbaldehyde, 4-methylthiazole-5- carbaldehyde, (E)-2-phenyl-3-(phenylthio)acrylaldehyde, cyclohexane-carbaldehyde, (E)-but-2- enal, undecanal, 3-methylbutanal, 4- fluorobenzaldehyde, 3-(trifluoromethyl)benzaldehyde, 4-

[0079] (trifluoromethyl)benzaldehyde, in presence of trifluoroacetic acid, phenylsilane and using toluene as solvent at 70 °C for a period of 16 h under the argon atmosphere to obtain the compound of Formula A.

[0080] The (E)-5-alkoxy-1 -phenylpentan-1 -one 0-(2-(A / ,A / -disubstitutedamino)ethyl) oximes of formula A produced by Scheme I, are:

[0081] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(benzyl(2,2,2- trifluoroethyl)amino)ethyl) oxime; A1

[0082] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((4- methoxybenzyl)(2,2,2- trifluoroethyl)amino)ethyl) oxime; A2

[0083] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((4-bromobenzyl)(2,2,2- trifluoroethyl)amino)ethyl) oxime; A3

[0084] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(((6- bromobenzo[d][1 ,3]dioxol- 5-yl)methyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime; A4

[0085] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((benzo[d]thiazol-2- PT / 2025 / 17225 ylmethyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime; A5

[0086] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(((5-bromothiophen-2- yl)methyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime; A6

[0087] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(((4-methylthiazol-5- yl)methyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime; A7

[0088] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(((E)-2-phenyl-3- (phenylthio)allyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime; A8

[0089] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2- ((cyclohexylmethyl)(2,2,2- trifluoroethyl)amino)ethyl) oxime; A9

[0090] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(((E)-but-2-en-1 - yl)(2,2,2- trifluoroethyl)amino)ethyl) oxime; A10

[0091] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((2,2,2- trifluoroethyl)(undecyl)amino)ethyl) oxime; A11

[0092] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(isopentyl(2,2,2- trifluoroethyl)amino)ethyl) oxime; A12

[0093] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((4-fluorobenzyl)(2,2,2- trifluoroethyl)amino)ethyl) oxime; A13

[0094] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((2,2,2-trifluoroethyl)(3-

[0095] (trifluoromethyl)benzyl)amino)ethyl)oxime; A14a and

[0096] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((2,2,2- trifluoroethyl)(4- (trifluoromethyl)benzyl)amino)ethyl) oxime; A15.

[0097] In another embodiment, the present invention provides a process for the preparation of compounds of formula A (Scheme II), wherein compound (2) is a ketone, comprising: PT / 2025 / 17225 reacting FLV (1 ) with reactant ketone (2), selected from cyclopentanone, cyclohexanone, hexan-2-one, in the presence of trifluoroacetic acid, phenylsilane and using toluene as solvent ata temperature of 1 10 °C for a period of 16h under argon atmosphere to obtain the compound of Formula A.

[0098] The (E)-5-alkoxy-1 -phenylpentan-1 -one 0-(2-(A / ,A / -disubstitutedamino)ethyl) oximes of formula A produced by Scheme II, are:

[0099] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(cyclopentyl(2,2,2- trifluoroethyl)amino)ethyl) oxime; A16

[0100] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(cyclohexyl(2,2,2- trifluoroethyl)amino)ethyl) oxime; A17 and

[0101] (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(hexan-2-yl(2,2,2- trifluoroethyl)amino)ethyl) oxime; A18

[0102] MATERIALS AND METHODS USED IN EXPERIMENTS

[0103] All the product mixtures were analyzed by thin layer chromatography. UV inactive compounds were visualized in staining solution and UV active compounds were detected with UV lamp (A = 254 nm). All the reactions were performed under inert atmosphere wherever required. NMR spectra (1HNMR,13C, DEPT) were recorded in 400 MHz spectrometer using CDCI3 solvent. ES1 -MS and HRMS spectra were recorded on LC-MS / MS and HRMS-6540-UHD machines. Optical rotations were measured on a Perkin Elmer polarimeter. Column chromatography was carried out with silica gel (60-120, 230-400 mesh).

[0104] EXAMPLES PT / 2025 / 17225

[0105] It should be understood that the disclosed examples are merely exemplary of the invention, which may be embodied in various forms. Therefore, the details disclosed herein are not to be interpreted as limiting but merely as the basis for the claims and as a basis for teaching one skilled in the art how to make or use the invention. The following examples are given by way of illustration only and therefore should not be construed to limit the scope of the present invention in any manner.

[0106] Table 1 : Reaction of FLV with various aldehydes and ketones in presence of TFA and phenylsilane using toluene as a solvent under argon atmosphere. PT / 2025 / 17225 aln all cases FLV (1 equiv), aldehyde / ketone (1 equiv), phenylsilane (2.5 equiv), trifluoroacetic acid (1 .75 equiv), and 0.5 mL of toluene was heated with stirring at 70-1 10 °C for 16 h.

[0107] ^All reactions were carried under argon atmosphere.

[0108] Example 1. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-1-one-O-(2- (benzyl(2,2,2- trifluoroethyl)amino)ethyl) oxime (A1): To a solution of FLV 1 (1 eq.) in toluene was added aldehyde 2 (1.0 eq.) and the resulting mixture was refluxed at 70 °C under an inert atmosphere for 10 minutes. Then trifluoroacetic acid (1.75 eq.) and further PhSiH3 (1 eq.) were added, and the reaction was again heated at 70 °C for 16 h. The completion of reaction was monitored by TLC. On completion, the reaction mixture was cooled to room temperature, diluted with water and extracted with ethyl acetate. The organic layer was dried under reduced pressure and the crude product was purified by silica gel column chromatography to give (A1) yields in the range of 81 % (Table 1 , entry 1 ).1H NMR (400 MHz, CDCI3) 57.72 (d, J = 8.1 Hz, 2H), 7.60 (d, J = 8.2 Hz, 2H), 7.38 - 7.23 (m, 5H), 4.30 (dd, J = 7.1 , 4.2 Hz, 2H), 3.90 (s, 2H), 3.35 (t, J = 6.0 Hz, 2H), 3.29 (s,3H), 3.28 - 3.18 (m, 2H), 3.05 (t, J = 5.6 Hz, 2H), 2.77 (t, J = 7.5 Hz, 2H), 1.66 - 1.53 (m, 4H);13C NMR (100 MHz, CDCI3) 6 157.3, 139.1 , 138.5, 130.9, 130.6, 128.7, 128.4, 127.4, 126.6, 125.4 (q, = 7.4, 3.6 Hz), 72.7, 72.2, 59.3, 58.6, 54.7 (q, = 30.4 Hz), 52.9, 29.6, 26.2, 23.1. HRMS (ESI) (m / z): [M+H]+calculated for C24H29F6N2O2, 491.2128; found, 491 .2132.

[0109] Example 2. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-1-one O-(2-((4- methoxybenzyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime (A2): This compound was synthesized using the similar procedure as described in example 1 (Table 1 , entry 2). PT / 2025 / 17225

[0110] 1H NMR (400 MHz, CDCI3) 5 7.71 (d, J =8.2 Hz, 2H), 7.60 (d, J = 8.3 Hz, 2H), 7.25 (dd, J= 6.9, 4.5 Hz, 2H), 6.87 - 6.79 (m, 2H), 4.29 (t, J = 5.7 Hz, 1 H), 3.82 (s, 2H), 3.77 (s, 3H), 3.35 (t, J = 6.0 Hz, 2H), 3.30 (s, 3H), 3.21 (q, J = 9.5 Hz, 2H), 3.02 (t, J = 5.6 Hz, 2H), 2.76 (t, J = 7.5 Hz, 2H), 1.66 - 1.53 (m, 4H).13C NMR (100 MHz, CDCI3) 6 158.9, 157.3, 139.1 , 130.4, 129.9, 126.5, 125.4 (q, J = 7.4, 3.6 Hz), 113.7, 72.6, 72.2, 58.7, 58.6, 55.2, 54.5 (q, J = 30.3 Hz), 52.7, 29.7, 26.2, 23.1. HRMS (ESI) (m / z): [M+H]+calculated for C25H31 F6N2O3, 521 .2233; found, 521 .2243.

[0111] Example 3. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-1-one O-(2-((4- bromobenzyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime (A3): This compound was synthesized using the similar procedure as described in example 1 (Table 1 , entry 3). 1 H), 1 .67 - 1 .56 (m, 2H).13C NMR (100 MHz, CDCI3) 6 157.4, 139.0, 137.7, 131.5, 131.4, 131.0, 130.4, 130.3, 127.3, 126.5, 125.4 (q, J = 3.7 Hz), 121.1 , 72.5, 72.2, 58.7, 58.6, 54.8 (q, J = 30.4 Hz), 52.9, 29.7, 26.3, 23.2. HRMS (ESI) (m / z): [M+H]+calculated for C24H28BrF6N2O2, 569.1233; found, 569.1243.

[0112] Example 4. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-1- one-O-(2-(((6-brornobenzo[ ][1 ,3]dioxol-5-yl)methyl)(2,2,2- trifluoroethyl)amino)ethyl) oxime (A4): This compound was synthesized using the similar procedure as described in example 1 (Table 1 , entry 4). PT72025 / 17225

[0113] 1.55 (m, 4H).13C NMR (100 MHz, CDCI3) 5 157.4, 147.6, 147.5, 139.1 , 131.0, 130.9, 130.6, 130.3, 130.0, 129.5, 127.2, 126.5, 125.4 (q, J = 7.5, 3.7 Hz), 124.4, 122.7, 113.9, 112.5, 110.0, 101.6, 72.3, 72.3, 58.8, 58.6, 55.0 (q, J = 30.5 Hz), 53.0, 29.6, 26.3, 23.1. HRMS (ESI) (m / z): [M+H]+calculated for C25H28BrF6N2O4, 613.1131 ; found, 613.1143.

[0114] Example 5. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-

[0115] 1-one-O-(2- ((benzo[d]thiazol-2-ylmethyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime

[0116] (A5): This compound was synthesized using the similar procedure as described in example 1 (Table 1 , entry 5).

[0117] 1

[0118] 7.4 Hz, 2H), 1.63 - 1.57 (m, 4H).13C NMR (100 MHz, CDCI3) 5 172.0, 157.6, 153.2, 135.3, 126.5, 126.0, 125.4 (q, J= 7.3, 3.7 Hz), 125.1 , 122.8, 121.8, 72.6, 72.2, 58.6,

[0119] 57.7, 55.5 (q, = 31 .0 Hz), 53.5, 29.7, 29.6, 26.3, 23.1 . HRMS (ESI) (m / z): [M+H]+calculated for C25H28F6N3O2S, 548.1801 ; found, 548.1808.

[0120] Example 6. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-1- one-O-(2-(((5- bromothiophen-2-yl)methyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime (A6): This compound was synthesized using the similar procedure as described in example 1 (Table 1 , entry 6). PT / 2025 / 17225

[0121] 1H NMR (400 MHz, CDCI3) 5 7.73 (d, J = 8.2 Hz, 2H), (d, J = 8.3 Hz, 2H), 6.88 (d, J = 3.7 Hz, 1 H), 6.69(d, J= 3.7 Hz, 1 H), 4.31 (t, J= 5.6 Hz, 2H), 4.03 (s, 2H), 3.36 (t, J = 5.9Hz, 2H), 3.31 (s, 3H), 3.25 (q, J = 9.4 Hz, 2H), 3.07 (t, J = 5.5 Hz,2H), 2.77 (t, 1 H), 1.63 - 1.57 (m, 4H).13C NMR (100 MHz, CDCI3) 6 157.5, 143.8, 139.0, 131.0, 130.7, 129.3,

[0122] 126.6, 126.3,125.4 (q, J = 3.7 Hz), 122.7, 111.9, 72.7, 72.2, 58.6, 54.3 (q, J = 36.5,

[0123] 24.5 Hz), 52.6, 29.7, 26.3, 23.1. HRMS (ESI) (m / z): [M+H]+calculated for C22H26BrF6N2O2S, 575.0797; found, 575.0807.

[0124] Example 7. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-1- one-O-(2-(((4- methylthiazol-5-yl)methyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime

[0125] (A7): This compound was synthesized using the similar procedure as described in example 1 (Table 1 , entry 7).

[0126] 1H NMR (400 MHz, CDCI3) 6 8.65 (s, 1 H), 7.72 (d, J= 8.2 Hz, 2H), 7.62 (d, J= 8.3 Hz, 2H), 4.31 (t, J = 5.6 Hz, 2H), 4.04 (s, 2H), 3.36 (t, J = 6.0 Hz, 2H), 3.30 (s, 3H), 3.24 (q, = 9.4 Hz, 2H), 3.06 (t, J= 5.6 Hz, 2H), 2.77 (t, 2H), 2.42 (s, 3H), 1.64 - 1.57 (m, 4H).13C NMR (100 MHz, CDCI3) 5 157.6, 151.5, 150.4, 139.0, 131.1 ,

[0127] 130.7, 129.2, 127.1 , 126.6, 125.4 (q, J = 7.5, 3.7 Hz), 124.3, 72.6, 72.2, 58.6, 54.2 (q, = 30.6 Hz), 52.7, 50.5, 29.7, 29.7, 26.3, 23.1 , 15.2. HRMS (ESI) (m / z): [M+H]+calculated for C22H28F6N3O2S, 512.1801 ; found, 512.1812. Example 8. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-1-one-O-(2-(((E)- 2-phenyl- 3-(phenylthio)allyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime (A8): This compound was synthesized using the similar procedure as described in example 1 (Table 1 , entry 8). PT / 2025 / 17225

[0128] 1H NMR (400 MHz, CDCI3) 5 7.70 (d, J = 8.2 Hz, 2H), 7.59 (d, J = 8.3 Hz, 2H), 7.42 - 7.25 (m, 10H), 7.23 - 7.19 (m, 1 H), 6.58 (s, 1 H), 4.25 (t, J = 5.7 Hz, 1 H), 3.76 (s, 1 H), 3.32 (t, J = 6.0 Hz, 2H), 3.29 (s, 3H), 3.24 (q, J= 9.4Hz, 2H), 3.08 (t, J = 5.7 Hz, 1 H), 2.72 - 2.64 (m, 2H),1 .59 - 1 .50

[0129] (m, 4H).13C NMR (100 MHz, CDCI3) 6 157.4, 139.0, 138.4, 137.2, 136.3, 131.0,

[0130] 130.7, 129.2, 129.1 , 128.3, 128.1 , 127.8, 126.7, 126.5, 125.4 (q, J= 3.6 Hz), 124.7,

[0131] 72.7, 72.2, 61.8, 58.6, 54.7 (q, J = 60.9, 30.5 Hz), 52.9, 29.6, 26.2, 23.1. HRMS(ESI) (m / z): [M+H]+calculated for C32H35N2O2SF6, 625.2318; found, 625.2321.

[0132] Example 9. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-

[0133] 1-one-O-(2- ((cyclohexylmethyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime, (A9):

[0134] This compound was synthesized using the similar procedure as described in example 1 (Table 1 , entry 9).

[0135] 1.21 - 1.14 (m, 2H), 0.89 - 0.77 (m, 2H).13C NMR (100 MHz, CDCI3) 5 157.2, 139.2, 130.8 (q, J = 32.6 Hz), 130.1 , 127.3, 126.5, 125.4 (q, J = 7.3, 3.7 Hz), 124.5,

[0136] 122.7, 120.0, 72.6, 72.3, 62.7, 58.6, 56.3 (q, J = 30.3 Hz), 54.0, 36.6, 31.2, 29.63, 26.8, 26.2, 26.1 , 23.1. HRMS (ESI) (m / z):[M+H]+calculated for C24H35F6N2O2,

[0137] 497.2597; found, 497.2611. PT / 2025 / 17225

[0138] Example 10. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-1-one O-(2-(((E)- but-2-en- 1-yl)(2,2,2-trifluoroethyl)amino)ethyl) oxime, (A10): This compound was synthesized using the similar procedure as described in example 1 (Table 1 , entry 10).

[0139] 1H NMR (400 MHz, CDCI3) <57.74 (d, J = 8.2 Hz, 1 H),7.61 (d, J = 8.3 Hz, 2H), 5.70 - 5.56 (m, 1 H), 5.53 - 5.42 (m, 1 H), 4.28 (m, 1 H), 3.37 (t, J = 6.0 Hz, 2H), 3.31 (s, 3H), 3.28 (d, J = 6.6

[0140] Hz, 2H), 3.15 (q, J = 9.5 Hz, 2H), 3.01 (t, J = 7.5, 4.0 Hz, 2H), 2.77 (t, J = 7.5 Hz, 2H), 1.76 - 1 .67 (m, 3H), 1 .65 - 1 .59 (m, 4H).13C NMR (100 MHz, CDCI3) 6 157.3,

[0141] 139.1 , 131.0, 130.6, 129.62, 127.4, 126.5, 125.4 (q, J = 3.7 Hz), 72.8, 72.3, 58.6, 57.4, 54.2 (q, J = 60.9, 30.5 Hz), 53.2, 29.7, 29.6, 26.2, 23.1 , 17.8. HRMS (ESI) (m / z): [M+H]+calculated for C21 H29F6N2O2, 455.2128; found, 455.2136.

[0142] Example 11. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-1-one O-(2- ((2,2,2- trifluoroethyl)(undecyl)amino)ethyl) oxime, (Al l): This compound was synthesized using the similar procedure as described in example 1 (Table 1 , entry 1 1 ).

[0143] 1H NMR (400 MHz, CDCI3) 5 7.74 (d, J = 8.1 Hz, 2H),7.61 (d, J = 8.2 Hz, 2H), 4.28 (t, J = 5.9 Hz, 2H), 3.37 (t, J= 7.7, 4.3 Hz, 1 H), 3.31 (s, 3H), 3.15 (q, = 9.5 Hz, 2H), 3.01 (t, J = 5.8 Hz, 2H), 2.79 - 2.74 (m, 1 H), 2.71 - 2.66 (m, 1 H), 1 .64 - 1 .55 (m, 4H), 1 .30 - 1 .21 (m, 18H), 0.88 (t, J =

[0144] 6.9 Hz, 3H).13C NMR(100 MHz, CDCI3) 5

[0145] 157.3,139.1 , 131.0, 130.6, 129.5, 127.3,126.5, 125.4 (q, J = 3.7 Hz), 124.5, 122.7, 72.7, 72.3, 58.6, 55.6 (q, = 30.5 Hz), 53.6, 31.9, 29.7,29.7,29.6, 29.6, 29.6, 29.4,

[0146] 27.6, 27.0, 26.2, 23.1 , 22.7, 14.1. HRMS (ESI) (m / z): [M+H]+calculated forC28H45F6N202, 555.3380; found, 555.3386. PT / 2025 / 17225

[0147] Example 12. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-1-one O-(2- (isopentyl(2,2,2-trifluoroethyl)amino)ethyl) oxime, (A12): This compound was synthesized using the similar procedure as described in example 1 (Table 1 , entry 12).1H NMR (400 MHz, CDCI3) 5 7.74 (d, J = 8.1 Hz, 2H), 7.61 (d, J = 8.3 Hz, 2H), 4.28 (t, J= 5.9 Hz, 1 H), 3.37 (t, J= 6.0 Hz, 2H), 3.31 (s, 3H), 3.15 (q, J = 9.5 Hz, 2H), 3.01 (t, J = 5.8 Hz, 2H), 2.80 - 2.74 (m, 2H), 2.74 - 2.68 (m, 2H), 1.65 - 1.56 (m, 2H), 1.39 - 1.33 (m, 1 H), 0.90 (s, 2H), 0.88 (s, 1 H).13C NMR (100 MHz, CDCI3) 6 157.3,139.2, 131.0, 130.6, 129.5, 127.3, 126.5, 125.4 (q, J = 3.8 Hz), 124.5, 122.7, 72.7, 72.3, 58.6, 55.5 (q, J = 30.3 Hz), 53.6, 53.6, 36.5, 29.6, 26.2, 25.8, 23.1 , 22.7. HRMS (ESI) (m / z): [M+H]+calculated for C22H33F6N2O2, 471 .2441 ; found, 471 .2450.

[0148] Example 13. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-1-one O-(2-((4- fluorobenzyl)(2,2,2-trifluoroethyl)amino)ethyl)oxime, (A13): This compound was synthesized using the similar procedure as described in example 1 (Table 1 , entry 13).

[0149] 1H NMR (400 MHz, CDCI3) 5 7.74 (d, J = 8.2 - 1.60 (m, 4H).13C NMR (100 MHz, CDCI3) 6

[0150] 163.4, 160.9, 157.4, 139.0, 134.2 (d, J = 3.2 Hz), 131.0, 130.7, 130.1 (d, J = 7.9 Hz), 127.3, 126.5, 125.4 (q, J = 3.8 Hz), 1 15.2 (d, = 21 .3 Hz), 72.6, 72.22, 58.6 (d, J = 5.0 Hz), 54.6 (q, J = 30.4 Hz), 52.8, 29.7, 26.3, 23.1. HRMS (ESI) (m / z): [M+H]+calculated for C24H28F7N2O2, 509.2034; found, 509.2046.

[0151] Example 14. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-1-one O-(2- ((2,2,2- trifluoroethyl)(3-(trifluoromethyl)benzyl)amino)ethyl)oxime, (A14): This compound was synthesized using the similar procedure as described in example 1 (Table 1 , entry 14). PT72025 / 17225

[0152] 1H NMR (400 MHz, CDCI3) 5 7.63 (d, J = 8.2 Hz, 2H), 7.53 (d, J = 8.1 Hz, 3H), 7.49 (d, J = 7.7 Hz, 1 H), 7.44 (d, J = 7.8 Hz, 1 H), 7.34 (t, J = 7.7 Hz, 1 H), 4.23 (t, J = 5.5 Hz, 2H), 3.88 (s, 2H), 3.27 (t, J = 5.9 Hz, 2H), 3.22 (s, 3H), 3.17 (q, J = 9.4 Hz, 2H), 2.99 (t, J = 5.5 Hz, 2H),

[0153] 2.69 (t, J = 7.4 Hz, 2H), 1.55 - 1.48 (m, 4H).13C NMR(100 MHz, CDCI3) 5 157.5,139.8, 139.0, 131.8, 130.8 (q, J = 32.3, 10.5 Hz), 128.9, 126.5, 125.4 (q, J = 3.8 Hz), 125.1 (q, J = 3.8 Hz), 124.3 (q, J = 3.6 Hz), 72.5, 72.2, 58.8, 58.5, 54.8 (q, J = 30.6 Hz), 53.0, 29.6, 26.2, 23.1. HRMS (ESI) (m / z): [M+H]+calculated for C25H28F9N2O2, 559.2002; found, 559.2054.

[0154] Example 15. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-1-one O-(2- ((2,2,2- trifluoroethyl)(4-(trifluoromethyl)benzyl)amino)ethyl) oxime, (A15): This compound was synthesized using the similar procedure as described in example 1 (Table 1 , entry 15).

[0155] 1H NMR (400 MHz, CDCI3) 5 7.63 (d, J = 8.2 Hz, 2H), 7.53 (d, J = 8.3 Hz, 2H), 7.48 (d, J = 8.1 Hz, 2H), 7.40 (d, J = 8.1 Hz, 2H), 4.22 (t, J = 5.5Hz, 2H), 3.89 (s, 2H), 3.27 (t, J = 5.8 Hz, 2H), 3.22 (s, 1 H), 3.17 (t, J = 9.4 Hz, 2H), 2.97 (t, J = 5.5

[0156] Hz, 2H), 2.69 (t, J = 7.4 Hz, 2H), 1 .56 - 1 .50 (m, 4H).13C NMR (100 MHz, CDCI3) 5 157.4, 142.9, 138.9,130.3 (q, J = 128.2, 32.2 Hz), 128.7, 127.2, 126.5, 125.4 (q, J = 8.7, 3.9 Hz), 124.4, 122.8, 122.7,72.4, 72.2, 58.9, 58.6, 54.9 (q, = 30.6 Hz), 53.0, 29.7, 26.3, 23.2. HRMS (ESI) (m / z): [M+H]+calculated for C25H27F9N2O2, 559.2002; found, 559.2001 .

[0157] Example 16. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-1-one O-(2- (cyclopentyl(2,2,2-trifluoroethyl)amino)ethyl) oxime, (A16): To a solution of FLV 1 (1.0 eq.) in toluene was added ketone 2 (1.0 eq.) and the resulting mixture was refluxed at 70 °C under an inert atmosphere for 10 minutes. Then trifluoroacetic acid (1 eq.) and further PhSiH3 (1 .0 eq.) were added, and the reaction was again heated PT / 2025 / 17225 at 1 10 °C for 16 h. The completion of reaction was monitored by TLC. On completion, the reaction mixture was cooled to room temperature, diluted with water and extracted with ethyl acetate. The organic layer was dried under reduced pressure and the crude product was purified by silica gel column chromatography to give (A16) yields in the range of 64% (Table 1 , entry 16).

[0158] 1H NMR (400 MHz, CDCI3) 57.74 (d, J= 8.2 Hz, 2H), 7.61 (d, J = 8.3 Hz, 2H), 4.30 (t, J = 6.1 Hz, 2H), 3.38 (t, = 6.0Hz, 2H), 3.31 (s, 3H), 3.27 (t, = 8.1 Hz, 1 H), 3.19 (q, = 9.5 Hz, 2H), 3.05 (t, J = 6.1 Hz, 2H), 2.77 (t, J = 7.5 Hz, 2H), 1.87 - 1.81 (m, 1 H), 1.70 - 1.51 (m, 8H), 1.45 -

[0159] 1.33 (m, 1 H).13C NMR (100 MHz, CDCI3) 6 157.2, 139.2, 130.8 (q, J = 32.3 Hz),

[0160] 129.5, 128.1 , 127.3, 126.5, 125.4 (q, J = 3.7 Hz), 124.5, 122.7, 73.0, 72.2, 64.7, 58.5,

[0161] 53.4 (q, J = 30.7 Hz), 52.1 , 29.7, 29.6, 26.2, 23.8, 23.1. HRMS (ESI) (m / z): [M+H]+calculated for C22H31 F6N2O2, 469.2284; found, 469.2291 .

[0162] Example 17. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-1-one O-(2- (cyclohexyl(2,2,2-trifluoroethyl)amino)ethyl) oxime, (A17): This compound was synthesized using the similar procedure as described in example 16 (Table 1 , entry 17).

[0163] 1H NMR (400 MHz, CDCI3) 5 7.75 (d, J = 8.2 Hz, 2H),7.61 (d, J = 8.3 Hz, 2H), 4.24 (t, J = 6.3 Hz,1 H), 3.38 (t, J = 6.0 Hz, 2H), 3.31 (s, 3H), 3.12 (q, = 9.4 Hz, 2H), 2.98 (t, J = 6.3 Hz, 2H), 2.77 (t, = 7.4 Hz, 2H), 2.60 -2.49 (m, 1 H), 1.81 (t, = 1 1 .9 Hz, 4H), 1 .67 - 1 .57 (m, 5H), 1 .29 - 1.08 (m, 5H).13C NMR (100 MHz, CDCI3) 5

[0164] 157.0, 139.3, 130. (q, J = 32.3 Hz), 128.2, 127.22, 126.5, 125.5, 125.3 (q, J = 3.6 Hz), 124.5, 122.8, 120.1 , 73.9, 72.2, 62.0, 58.5, 52.9 (q, J= 31 .2 Hz), 51.1 , 29.6, 29.6, 26.1 , 26.0, 26.0, 23.1. HRMS (ESI) (m / z): [M+H]+calculated for C23H33F6N2O2, 483.2441 ; found, 483.2447.

[0165] Example 18. (E)-5-methoxy-1-(4-(trifluoromethyl)phenyl)pentan-1-one O-(2- PT / 2025 / 17225

[0166] (hexan-2- yl(2,2,2-trifluoroethyl)amino)ethyl) oxime, (A18): This compound was synthesized using the similar procedure as described in example 16 (Table 1 , entry 18).

[0167] 1H NMR (400 MHz, CDCI3) 5 7.74 (d, J = 8.2 Hz, 2H),7.61 (d, J = 8.3 Hz, 2H), 4.27 - 4.18 (m, 2H), 3.38 (t, = 6.0 Hz,1 H), 3.31 (s, 1 H), 3.13 - 3.01 (m, 2H), 2.99 -2.84 (m, 2H), 2.81 - 2.71 (m, 3H), 1.66 - 1.56 (m, 2H),1.32 - 1.24 (m, 4H), 0.99 (d, J = 6.6 Hz, 3H), 0.89 (t, =7.0 Hz, 2H).13C NMR (100 MHz,CDCl3) 6 157.0, 139.3,130.7 (q, J = 32.3 Hz), 127.3, 126.5, 125.4 (q, J

[0168] = 3.8 Hz), 124.5, 122.7,73.7, 72.3, 58.6, 57.8, 52.8 (q, J = 31.1 Hz), 50.4, 34.2, 29.72, 29.6, 29.0,26.1 , 23.1 , 22.8, 15.3,14.1. HRMS (ESI) (m / z): [M+H]+calculated for C23H35F6N2O2, 485.2597 ; found, 485.2610.

[0169] BIOLOGICAL EVALUATION PT / 2025 / 17225

[0170] ANTIVIRAL ACTIVITY OF THE CANDIDATE MOLECULES:

[0171] SARS-CoV2 virus was propagated in Vero cells. The anti-COVID activity of candidate molecules were done in cell-based assays. Briefly, Vero cells were cultured in DMEM medium supplemented with 10% FBS, and were maintained at 37 °C and 5% CO2 in the incubator.

[0172] Primarily, the candidate molecules were tested for the cytotoxicity using MTT Assay. The cells were seeded in 96 well culture plate and allowed to form a monolayer at 75-80 % confluence at 37 °C with 5% CO2. The drug candidates were added to the cells at different concentrations such as 10 pM, 5 pM, 2.5 pM, 1.25 pM, 0.625 pM. 24 hours post treatment, the media containing the drug was removed and the cells were incubated with 200 pl (1 mg / ml) of MTT substrate for 2 hours at 37 °C with 5% CO2. Formazan crystals formed were observed under the microscope and the crystals were dissolved in 100 pl of DMSO. The absorbance was measured at 570 nm in Multimode Micro plate reader (Synergy HIM) and the cytotoxicity was calculated using the standard methods.

[0173] The concentrations that were not cytolytic were considered for the anti-viral studies. Briefly, the Vero cells were cultured in 96 well culture plate and incubated at 37 °C with 5% CO2. At 70-80 % confluency, the cells were infected with SARS CoV2 viral PT / 2025 / 17225 particles (MOI 0.1 ) suspended in serum free DMEM (50 pl / well). The infection media was maintained for 3 hours at the same culture conditions. After 3 hours, the viral inoculum was replaced with 200 pl of different concentrations of candidate drugs (5 pM, 1 pM and 0.5 pM) prepared in fresh DMEM media containing 10 % FBS. Six replicates were set up for each drug concentration. The media containing the drug was incubated with the cells for 72 hours at 37 °C with 5 % CO2. Post incubation, the cell free supernatant from each well of the experimental groups was carefully collected into the square Deepwell plates (Deepwell Pyramid Bottom Kingfisher styleTarsons) and stored at -80 °C until further use.

[0174] Viral RNA from the collected supernatant was isolated using the automated Kingfisher Flex (version 1.01 , Thermo Scientific) according to the manufacturer’s instructions. The virions in the collected supernatant were lysed using the pre-filled lysis buffer in the HiPurA® Pre-filled Plates (HiMedia) along with 10 pl of the magnetic beads, 5 pl of Proteinase K and 5 pl of carrier RNA. The isolated RNA was collected in the elution buffer from MagMAX extraction Kit (Applied Bio- Systems, Thermofisher) and stored at -80eC until further use.

[0175] Quantification of the resultant viral RNA was done using RT-qPCR method (QuantStudioTM5 Re-al- Time PCR - Applied Biosystems) for both the treated and viral control groups. SARS CoV2 specific viral gene primers were obtained commercially with the kit (One-step RT-qPCR kit Meril Diagnostics Pvt. Ltd). The kit is designed to detect SARS-CoV2 virus gene such as Open Reading Frame (ORFI ab)-gene, Nucleoprotein (N)-gene and the host endogenous RNaseP-gene (Internal Control gene) under FAM, HEX and ROX channels respectively. The raw data was interpreted to determine the anti-viral activity of the drug candidates in the form of percentage viral reduction considering the N gene. The Log viral particles of both treated and viral control groups were calculated using the established standard equation of the RNA extracted from the tittered virus stock by RT-qPCR, using N- gene specific to SARS CoV-2 virus. The Relative Viral RNA (%) for the candidate drug molecules were calculated by comparing the log viral particles with the viral control. Candidate drug molecules showing more than 90 % reduction of SARS-CoV2 viral RNA at 0.5 pM were considered to derive the EC50 values. The EC50 values for the selected candidate drugs were calculated by treating the cells with different PT / 2025 / 17225 concentrations (0.025 pM, 0.05 pM, 0.1 pM, 0.2 pM, 0.4 pM, 0.6 pM, 0.8 pM and 1.6 pM) and the experiment was conducted as described above. The Dose-Response curves were generated by plotting Relative Viral RNA (%) against log concentration (nM) of the tested compounds through the Non-linear regression analysis (GraphPad Prism version 8.4.2).

[0176] The tested candidate molecules, A1, A3, A14, and A15 showed EC50 values of 0.108 pM, 0.091 pM, 0.141 pM, and 0.246 pM respectively.

[0177] ADVANTAGES OF THE INVENTION

[0178] The main advantages of the present invention are:

[0179] 1 . The present invention deals with one-pot process for the preparation of (E)-5- alkoxy-1 - phenylpentan-1 -one 0-(2-(A / ,A / -disubstitutedamino)ethyl) oximes.

[0180] 2. The invention leads to novel potent antiviral compounds (A1 & A3).

[0181] 3. The invention uses the commercially available trifluoroacetic acid as CF3 source.

[0182] 4. The molecules show non-cytotoxicity, indicating A1 & A3 as a safe antiviral candidate.

[0183] 5. The molecules (A1, A3, &A14) show percent viral reduction greater than 95% at 5 pM, 1 pM, 0.5 pM concentrations, indicating significant viral reduction potential.

Claims

PT / 2025 / 17225WE CLAIM:1 . A compound of general formula A or a salt thereof;Formula AJ wherein Ri is selected from the group consisting of substituted or unsubstituted: aryl, heteroaryl, aliphatic ketones, cycloalkyl, alkyl, and alkenyl;R2 is selected from the group consisting of hydrogen, substituted or unsubstituted alkyl and substituted or unsubstituted aryl or R1 and R2 may together form a substituted or unsubstituted cycloalkyl group; andR3 is a haloalkyl.

2. The compound as claimed in claim 1 , wherein the substitutent on R1 is selected from the group consisting of alkyl, alkoxy, halo, trifluoroalkyl, alkenyl, thiophenyl and aryl.

3. The compound as claimed in claim 1 , selected from the group consisting of:(E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(benzyl(2,2,2- trifluoroethyl)amino)ethyl) oxime; A1(E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((4- methoxybenzyl)(2,2,2- trifluoroethyl)amino)ethyl) oxime; A2(E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((4- bromobenzyl)(2,2,2- trifluoroethyl)amino)ethyl) oxime; A3(E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(((6-PT / 2025 / 17225 bromobenzo[d][1 ,3]dioxol-5-yl)methyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime; A4 (E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((benzo[d]thiazol-2- ylmethyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime; A5(E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(((5-bromothiophen-2- yl)methyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime; A6(E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(((4-methylthiazol-5- yl)methyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime; A7(E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(((E)-2-phenyl-3- (phenylthio)allyl)(2,2,2-trifluoroethyl)amino)ethyl) oxime; A8(E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2- ((cyclohexylmethyl)(2,2,2- trifluoroethyl)amino)ethyl) oxime; A9(E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(((E)-but-2-en-1 - yl)(2,2,2- trifluoroethyl)amino)ethyl) oxime; A10(E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((2,2,2- trifluoroethyl)(undecyl)amino)ethyl) oxime; A11(E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(isopentyl(2,2,2- trifluoroethyl)amino)ethyl) oxime; A12(E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((4-fluorobenzyl)(2,2,2- trifluoroethyl)amino)ethyl) oxime; A13(E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-((2,2,2-trifluoroethyl)(3- (trifluoromethyl)benzyl)amino)ethyl)oxime; A14(E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one O-(2-((2,2,2- trifluoroethyl)(4- (trifluoromethyl)benzyl)amino)ethyl) oxime; A15(E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(cyclopentyl(2,2,2- trifluoroethyl)amino)ethyl) oxime; A16(E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(cyclohexyl(2,2,2- trifluoroethyl)amino)ethyl) oxime; A17 andPT / 2025 / 17225(E)-5-methoxy-1 -(4-(trifluoromethyl)phenyl)pentan-1 -one-0-(2-(hexan-2-yl(2,2,2- trifluoroethyl)amino)ethyl) oxime; A18.

4. A process for the preparation of compounds of formula A, wherein the process comprises:reacting compound (1 ) with compound (2), wherein R1 is selected from the group consisting of substituted or unsubstituted: aryl, heteroaryl, aliphatic ketones, cycloalkyl, alkyl, and alkenyl; Ffc is selected from the group consisting of hydrogen, substituted or unsubstituted alkyl and substituted or unsubstituted aryl or Ri and R2 may together form a substituted or unsubstituted cycloalkyl group and compound (3) wherein R3 is a haloalkyl, in presence of phenylsilane and a solvent at a temperature range of 70 °C to 110 °C for a period of 16 h under the argon atmosphere to obtain the compound of Formula A.

5. The process as claimed in claim 4, wherein (2) is an aldehyde selected from the group consisting of benzaldehyde, 4- methoxybenzaldehyde, 4- bromobenzaldehyde, 6-bromobenzo[d][1 ,3]dioxole-5-carbaldehyde, benzo[d]thiazole-2-carbaldehyde, 5-bromothiophene-2-carbaldehyde, 4- methylthiazole-5- carbaldehyde, (E)-2-phenyl-3-(phenylthio)acrylaldehyde, cyclohexane-carbaldehyde, (E)-but-2- enal, undecanal, 3-methylbutanal, 4- fluorobenzaldehyde, 3-(trifluoromethyl)benzaldehyde, 4-(trifluoromethyl)benzaldehyde.

6. The process as claimed in claim 5, wherein (2) is a ketone selected from the group consisting of cyclopentanone, cyclohexanone and hexan-2-one.

7. The process as claimed in claim 4, wherein (3) is trifluoroacetic acid.

8. The process as claimed in claim 4, wherein the solvent used is toluene.PT / 2025 / 172259. The process as claimed in claim 4, wherein the temperature is 70 °C.

10. The process as claimed in claim 4, wherein the Yeild of compounds of formula A is 58 to 81%.

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