200 results about "Formyl group" patented technology

The invention discloses a porphyrin-based covalent organic framework nano material, a preparation method and application of the porphyrin-based covalent organic framework nano material in polyurethane, and belongs to the field of functional nano materials and antibacterial materials. The porphyrinyl covalent organic framework nano material is prepared from 5, 10, 15, 20-tetra (4-aminophenyl) porphyrin and bis-(5-formyl furfuryl) ether through a Schiff base reaction, and the structural formula of the porphyrinyl covalent organic framework nano material is # imgabs0. The porphyrinyl covalent organic framework nano material prepared by the invention has relatively high photothermal conversion efficiency when being used as a photothermal agent, and has a relatively good sterilization effect under the condition of relatively low concentration. Besides, based on the porphyrin-based covalent organic framework nano material, a WPUS / Por-COF composite film is prepared, the composite film has excellent mechanical properties and excellent photothermal conversion efficiency, and has a good sterilization effect under the condition of relatively low concentration, bacteria can be inactivated within a short time, and the sterilization rate can reach 99% or above.

The invention belongs to the technical field of pesticides, and particularly relates to a pyridyl alkoxy pyrimidine compound and application thereof. The compound is shown as a formula I: # imgabs0 #, wherein X and Y respectively and independently represent hydrogen, hydroxyl, alkyl, alkoxy, alkenyloxy, alkynyloxy and the like; z represents hydrogen, halogen, a cyano group, an amino group, a nitro group, a formyl group, a cyano alkyl group, a hydroxyalkyl group, an alkyl group, an alkenyl group, an alkynyl group and the like. The compound or the salt thereof has an excellent effect as an agricultural and horticultural insecticide.

The invention discloses a preparation method of a grafted and substituted thiophene polymer material, which comprises the following steps: mixing poly (3-hexylthiophene), a grafting monomer, a catalyst and an auxiliary agent, and heating for reaction to obtain the grafted and substituted thiophene polymer material, the structural formula of the grafting monomer is as shown in formula (I); wherein B is fluorine, chlorine, bromine or iodine, A is a carbon atom or a nitrogen atom, and R is cyano, formyl, methoxycarbonyl or; according to the method, pre-synthesis of complex functional monomers is avoided, the main chain of the poly (3-hexylthiophene) can be directly modified without using an expensive catalyst or ligand, the polymerization reaction of the poly (3-hexylthiophene) is not interfered, and meanwhile, the method has the advantages of simplified steps and low cost.

The invention discloses a fluorescent covalent organic framework material for hydrogen sulfide detection as well as a preparation method and application thereof, relates to a covalent organic framework material as well as a preparation method and application thereof, and aims to solve the technical problems that an existing porous material for H2S detection is few in structure type, unstable in COFs (Covalent Organic Frameworks) structure, high in detection limit and harsh in detection environment. The periodic structure fragment of the fluorescent covalent organic framework material for hydrogen sulfide detection is shown in the specification. 3-(5, 10-diamino-1H-phenanthrene) [9, 10-d] imidazole-2-yl) phenol and 2, 4, 6-tri (4-formylphenoxy)-1, 3, 5-triazine are subjected to a reaction to obtain a hydroxyl intermediate, the hydroxyl intermediate is modified with 2, 4-dinitrofluorobenzene, and the fluorescent material is used for qualitative detection of H2S. The method is not interfered by amino acids and anions in the environment, and is not influenced by an acid-base environment. The method can be used in the field of H2S detection.

The invention discloses a C60-BODIPY triplet photosensitizer as well as a preparation method and photodynamic antibacterial application thereof. In the preparation process, a fullerene pyrrole ring compound and a BODIPY molecule are connected together through a benzene bridge group, and two ends of a bridge bond are respectively connected to a C atom on a fullerene pyrrole ring and a 6th site of the BODIPY molecule; a BODIPY-C60 binary molecule is formed; the preparation method comprises the following steps: reacting 9-anthracene formaldehyde with 2, 4-dimethyl pyrrole to generate a boron-dipyrromethene molecule of which the meso position is substituted by 9-anthryl, brominating the boron-dipyrromethene molecule at the 6 position by N-bromosuccinimide, coupling the boron-dipyrromethene molecule with p-formylphenylboronic acid, and carrying out Prato reaction on the coupled boron-dipyrromethene molecule with C60 and N-methylglycine to prepare the BODIPY-C60 binary triplet photosensitizer. The triplet photosensitizer has excellent photodynamic activity and relatively high reactive oxygen quantum yield, and can effectively kill bacteria.

The present invention relates to the preparation of cyantraniliprole, comprising the preparation of 8-methyl-2,4-dioxo-1,4-dihydro-2H-benzo[d][1,3]oxazine-6-carbonitrile key intermediate via 2-amino-5-((hydroxyimino)methyl)-3-methylbenzoic acid. Wherein hydroxylamine attacks a benzylic formyl group, to obtain the 2-amino-5-((hydroxyimino)methyl)-3-methylbenzoic acid, that undergoes simultaneously or by consecutive steps dehydrogenation and cyclization to obtain the benzo[d][1,3]oxazine group and the cyano group of the desired product. In addition, an improved method for the synthesis of the benzylic formyl group is also displayed.

The invention provides a preparation method and application of an ultrahigh crystalline fluorinated COFs (covalent organic frameworks) material, the ultrahigh crystalline fluorinated COFs material is prepared by reaction of fluorine-containing aldehyde monomer 2 ', 4', 6 '-trifluoro-5'-(4-formyl phenyl)-[1, 1 ': 3', 1 '-terphenyl]-4, 4'-dicarboxaldehyde and amine monomer, and the amine monomer is N1, N1-bis (4-aminophenyl) benzene-1, 4-diamine trihydrochloride or 1, 3, 5-tris (4-aminophenyl) benzene. The fluorinated COFs can efficiently capture Th (IV) ions from an aqueous solution, and the material has the advantages of high crystallinity, large adsorption capacity and excellent recycling performance.

The invention discloses a monatomic electrocatalyst of a metal polyphenol network as well as a preparation method and application of the monatomic electrocatalyst. The preparation method comprises the following steps: adding an alkaline solution of Pluronic F127; polyphenol and formaldehyde are added for a cross-linking reaction; dropwise adding a metal salt solution, stirring and mixing, carrying out a hydrothermal reaction, carrying out centrifugal separation to obtain a precipitate, and washing and drying to obtain the monatomic catalyst. According to the method, polyphenol containing a large number of hydroxyl groups is taken as a ligand, coordination with metal ions is realized through formaldehyde-assisted crosslinking, a reaction path is precisely regulated and controlled through hydrogen bond engineering, a CO2 reduction reaction path is changed from a traditional * CO path to a low-energy barrier formyl path, C-C chemical coupling and hydrogen evolution / deuterium evolution side reaction are synchronously inhibited, and the reaction efficiency is improved. The selectivity of methane or deuterated methane is obviously improved, the operation stability for ultra-long time is realized, and an effective solution is provided for synthesis of methane and deuterated methane with high additional value.

The invention discloses a 2-amino-4-(5-cyano-1-isopropyl-1H-indole-3-yl) pyrimidine compound and application thereof, the compound has the following structural general formula: in the formula, substituent R is substituted phenyl, the number of substituent groups on the benzene ring of the substituted phenyl is 1-2, and the substituent groups on the benzene ring of the substituted phenyl are 1-2. Substituent groups are respectively and independently selected from nitro, cyano, halogen, carbamoyl, furyl or pyridyl. The 2-amino-4-(5-cyano-1-isopropyl-1H-indole-3-yl) pyrimidine compound designed and synthesized by the invention is a novel efficient NF-kappa B induced kinase (NIK) inhibitor, and is suitable for drug development taking NF-kappa B induced kinase (NIK) as a target spot, and the obtained drug can be used for treating malignant tumors such as leukemia, multiple myeloma and the like.

The invention relates to a method for converting an N-formyl-protected amine into the corresponding deprotected amine, characterized in that the N-formyl-protected amine is deprotected by decomposing the formyl into carbon dioxide and hydrogen in the presence of water and a dehydrogenation catalyst and at a temperature in the range of 10 DEG C to 300 DEG C. The process can be used to effectively deprotect an N-formyl-protected amino alcohol intermediate in a process for preparing an amino alcohol by reductive hydrolysis of a nitrile functional group starting from an N-formyl-protected amino nitrile followed by deprotection of the N-formyl-protected amino alcohol intermediate.

The present invention provides a compound with which a molecular probe capable of distinguishing NSCs from CSCs can be produced, and a method for detecting cancer stem cells using the compound. The present invention relates to a compound having a formyl group, a substrate moiety, a quenching moiety, and a luminescent moiety that is non-luminous due to the quenching moiety, wherein the luminescent moiety may be rendered luminous by detaching the substrate moiety by a substrate-degrading enzyme and also converting the formyl group to a carboxy group by an aldehyde dehydrogenase to allow the quenching moiety to dissociate.

This invention relates to a potassium ion-responsive hydrogel based on iminoboronic ester bonds, its preparation method, and its applications. The hydrogel is prepared using guanosine, 2-formylphenylboronic acid, and polyoxyethylenediamine. The diol of guanosine forms a borate ester bond with 2-formylphenylboronic acid, and the primary amine in the polyoxyethylenediamine forms an imino group with the aldehyde group of 2-formylphenylboronic acid. The bases of guanosine form a G-quadruplex under the influence of potassium ions. The hydrogel has a porous network structure. The preparation method is as follows: A mixed aqueous solution of guanosine, 2-formylphenylboronic acid, and polyoxyethylenediamine is heated to boiling to obtain a clear solution. After cooling, the solution is mixed with a potassium ion solution to prepare the potassium ion-responsive hydrogel based on iminoboronic ester bonds. Compared with the prior art, the hydrogel prepared by this invention exhibits both temperature and potassium ion responsive characteristics.

The present application relates to the technical field of biological medicines. Specially, disclosed are a 2-arylbenzimidazole compound, and a preparation method therefor and the use thereof. The 2-arylbenzimidazole compound provided by the present application is a compound as shown in general formula I, or a pharmaceutically acceptable salt, isomer, solvate, hydrate, prodrug or isotope derivative thereof. The general formula I has a structural formula as follows: in the general formula I, R represents 1, 2, 3 or 4 identical or different substituents present on a benzene ring, and R is independently selected from the following groups: hydrogen, halogen, cyano, hydroxyl, optionally substituted C1-6 alkoxy, optionally substituted amino, optionally substituted formyl, optionally substituted sulfonyl, optionally substituted heterocycloalkyl, optionally substituted aryl, or optionally substituted heteroaryl. The 2-arylbenzimidazole compound of the present application exhibits an excellent inhibitory activity against BCR-ABL kinase, and is expected to be developed into a drug for treating and / or preventing BCR-ABL-related diseases.

The invention relates to an inhibitor for efficiently separating copper and sulfur under a low-alkalinity condition, a flotation reagent and a flotation method. The inhibitor is a compound as shown in a formula I (formula I), wherein R1, R2, R3 and R4 are respectively and independently selected from one of-R5X,-X,-H and-N + R6, R5 is alkyl of C1-C10, naphthenic base of C3-C10 or heterocyclic group of C3-C10, and the ring of the heterocyclic group is provided with or not provided with a substituent group; x is one of F, Cl, Br, I, tertiary amine positive ions, nitro, cyano, sulfo, formyl, acyl and carboxyl; r6 is a C1-C5 alkyl group or a C3-C5 cycloalkyl group; the inhibitor is low in viscosity and good in fluidity, pyrite and chalcopyrite in complex copper sulfide ore copper-sulfur ore can be effectively separated under the low-alkalinity condition, and the separation effect is remarkable.

Provided are a metal extractant for extracting metal ions present in a water phase to an oil phase, and a separation recovery method of metal ions. In the metal extractant, nitrogen atoms positioned at both terminals of a molecular chain forming the metal extractant do not form a carbamoyl bond and include an unsubstituted hydrocarbon group and a group including and any coordinating functional group in a group G1 of coordinating functional groups below as a coordinating functional group (a) for metal ions to be extracted, or include an unsubstituted hydrocarbon group. The separation recovery method includes mixing an oil phase including the metal extractant and a water phase including plural kinds of metal ions.

A process for the preparation of a compound of the sterically hindered alkoxyamine class is described, the process comprises the step of alkylating a sterically hindered hydroxylamine compound to a corresponding sterically hindered alkoxyamine by reacting said sterically hindered nitroxyl compound with a compound capable of producing a carbon-central alkyl radical, typically a territorial or secondary alkyl radical, the compounds capable of generating carbon-center alkyl radicals are selected from thermal radical initiators that form radical species in the temperature range of 40 DEG C to 200 DEG C, and from photoinitiators that undergo light excitation when irradiated with UV light or visible light in the range of 180 to 700 nm, in particular UV light in the range of 180 to 380 nm, the compounds capable of generating carbon center alkyl radicals are typically selected from the class of organic peroxides, azo compounds, benzoyl derivatives, benzophenone derivatives, thioxanthone derivatives, benzoin derivatives, benzoyl phosphine oxide derivatives, and the like. The invention relates to a peroxide, for example, selected from the group consisting of diacyl peroxides of formula (A), peracid esters of this formula (A), and oxalic acid peracid esters of formula (D) R-CO-O-O-Z-R (A), r-Z ''-X-CO-CO-O-O-Z''-R (D) wherein each R independently represents a primary or secondary alkyl or cycloalkyl group, preferably comprising from 1 to 15 carbon atoms, and X is oxygen-O-or peroxy-O-O-, Z represents CO or an alkylene group bonded to a quaternary carbon atom, the quaternary carbon atom being an alkylene group of formula (C) R '-C-R' (C), wherein each R'is selected from alkyl groups having 1 to 15 carbon atoms, and Z "represents the alkylene group bonded to a quaternary carbon atom having the formula (C). The described process produces the corresponding O-alkylated derivatives of the sterically hindered hydroxylamines, typically compounds of the class referred to as N-O-alkyl HALS, with very high selectivity and conversion and without the need for the use of catalysts, in particular metal catalysts.

Provided herein are methods for preparing crystalline forms of (R)-5-carbamoylpyridin-3-yl-2-methyl-4-(3-(trifluoromethoxy)benzyl)piperazine-1-carboxylate.

The application relates to the technical field of organic synthesis, and discloses a synthesis method of a benzoyl modified nucleoside, which comprises the following steps: dissolving or suspending a substrate in a solvent, adding N-chlorosuccinimide, reacting at a certain temperature, generating a corresponding N-chloroamine intermediate, then adding a certain equivalent of benzaldehyde, and generating a final product under the joint action of an oxidant and a catalyst. According to the method, the hydroxyl group on the sugar ring does not need to be protected, and is directly reacted with the amino group on the base, so that the side reaction is less, the obtained product is high in purity, and the yield is high.

The invention discloses a quasi-three-dimensional covalent organic framework material based on a two-dimensional substrate piled functional group, a preparation method and application of the quasi-three-dimensional covalent organic framework material in iodine adsorption, and the preparation method comprises the following steps: carrying out hydrothermal reaction on a mixture containing a phenyl compound, hexane (4-formylphenoxy) cyclotriphosphazene, 4-dimethylaminopyridine and water to obtain the quasi-three-dimensional covalent organic framework material based on the two-dimensional substrate piled functional group. The quasi-three-dimensional covalent organic framework material based on the two-dimensional substrate piled functional groups is obtained. According to the invention, a similar three-dimensional pore network is formed by orderly stacking two-dimensional substrates, and the three-dimensional covalent organic framework material has the characteristics of high specific surface area and strong structural stability of a three-dimensional covalent organic framework material; meanwhile, the problems that two-dimensional covalent organic framework materials are easy to peel off between layers and adsorption and mass transfer are limited are effectively solved, the defects that three-dimensional covalent organic framework materials are high in synthesis difficulty and poor in photoelectric property are avoided, and collaborative optimization of stability, adsorption efficiency and functional suitability is achieved.

The invention discloses a method for preparing an olaparib key intermediate compound as shown in a formula (1). The method comprises the following steps: (a) reacting a compound as shown in a formula (2) with a compound as shown in a formula (3) to generate a compound as shown in a formula (4); (b) carrying out intramolecular cyclization on the compound as shown in the formula (4) under the catalysis of acid to generate a compound as shown in a formula (5); (c) hydrolyzing the compound as shown in the formula (5) in an alkali solution, and acidifying to obtain a compound as shown in a formula (1); wherein in the compounds as shown in the formula (3), the formula (4) and the formula (5), R is formyl, acetyl, propionyl, butyryl, benzoyl, methoxycarbonyl, ethoxycarbonyl, t-butyloxycarbonyl, methylsulfonyl, benzenesulfonyl or p-toluenesulfonyl. The invention also discloses a compound shown in a formula (4) or a formula (5). The method is high in yield, mild in reaction condition, easy to purify and suitable for industrial large-scale production. # imgabs0 #

The application discloses a synthesis method of 3,3-difluorocyclopentylamine hydrochloride, and particularly relates to the technical field of chemical synthesis. The synthesis method comprises the following steps: taking 2-cyclopentenone and phthalimide as raw materials, and sequentially performing a Michael addition reaction, deoxygenation fluorination, removal of a phthaloyl protecting group, Boc protection and deprotection and salt formation reaction to obtain 3,3-difluorocyclopentylamine hydrochloride. The synthesis route and process design of the application are reasonable, the starting raw material is 2-cyclopentenone, the required reaction condition is mild, the post-treatment method is simple, the operability is strong, the raw material and reagent are cheap and easy to obtain, and the total yield can reach 43.6%, so the synthesis method has large-scale preparation value.

The application discloses a synthesis method of aromatic aldehyde, comprising the following steps: under inert atmosphere, a compound shown in formula I and a compound shown in formula II are reacted in an organic solvent containing a photocatalyst, a nickel catalyst, a ligand, a base and water under blue light irradiation to obtain aromatic aldehyde shown in formula III; formula I, formula II and formula III are structures as follows, ring A is selected from benzene, pyridine, thiophene, furan, pyridazine, indazole, indole, isoquinoline, quinoline, naphthalene, benzothiophene, dibenzofuran or dibenzothiophene; the application generates formyl radicals under the nickel synergistic photo-oxidation and reduction catalytic condition, and the formylation of bromobenzene and its derivatives is realized in a simple and efficient one-pot way, aromatic aldehyde is constructed, and the reaction has the characteristics of cheap and easily available raw materials, mild reaction conditions, controllable synthesis process, high separation yield / yield, green environmental protection, wide substrate applicability and the like.

The invention discloses a novel 3-formyl-2-methyl-4-(methylthio) benzoate compound as shown in a general formula VI, wherein R is an ester group, carboxylic acid, amide or cyano group. The invention also provides a synthesis method of the intermediate shown in the formula VI and application of the intermediate in preparation of topramezone. The reaction selectivity for preparing topramezone by using the formula VI is higher, and the whole process route is more suitable for realizing industrial production;

The present invention discloses an A,A'-bipyridinehydrazone-functionalized conjugated pillar[5]arene macrocyclic molecule and a synthesis method thereof. The invention comprises reacting a bis(4-formylphenylboronic acid)-functionalized pillar[5]arene with 2-hydrazinepyridine through an imine condensation reaction to obtain an A,A'-bipyridinehydrazone-functionalized conjugated pillar[5]arene PYP5 having two rigid functional arms. The macrocyclic molecule PYP5 can self-assemble through multiple hydrogen bonds to form a supramolecular polymer network. Thanks to the "double-arm-macrocyclic synergistic effect" between the double arms of the pillar[5]arene and the ethoxy group, PYP5 can provide multiple "clustered hydrogen bonds" to tightly bind ClO4. − Therefore, the supramolecular polymer network can effectively treat ClO4 in water. − It can show good adsorption and separation performance and can effectively remove ClO4 in water − The removal rate can reach 99.24%. The A,A'-bispyridinehydrazone functionalized conjugated column[5] aromatic macrocyclic molecule provided by the present invention has good application prospects in the fields of supramolecular assembly, water pollutant removal, adsorption separation, etc.

This invention discloses a hydrazone-linked fluorine-substituted covalent organic framework material, its preparation method, and its applications, belonging to the field of semiconductor photocatalysis technology. The material is synthesized by hydrazone condensation of 1,3,5-trifluoro-2,4,6-tris(4-formylphenyl)benzene and terephthalohydrazide, denoted as F-TPDH-COF. A one-step solvothermal synthesis is employed, resulting in a mild, environmentally friendly, low-cost, and easily scalable process. The material obtained by this invention utilizes hydrazone bonds to achieve proton enrichment in acidic media, and fluorine atoms regulate the electronic structure to improve charge separation efficiency. Under pH=2 conditions, the photocatalytic hydrogen peroxide production rate reaches as high as 5825.2 μmolg. ‑1 h ‑1 Its activity and stability are significantly better than most existing COF photocatalytic materials, and it can be used for efficient photocatalytic preparation of hydrogen peroxide in acidic systems, showing good prospects for industrialization.

The invention belongs to the field of organic synthesis, and particularly discloses an acoustic resonance synthesis method of 1, 4-diformyl-2, 3, 5, 6-tetrahydroxypiperazine, which comprises the following steps: under acoustic resonance and room temperature conditions, formamide, glyoxal and alkali liquor are subjected to a reaction for 5-10 min to synthesize 1, 4-diformyl-2, 3, 5, 6-tetrahydroxypiperazine, and the 1, 4-diformyl-2, 3, 5, 6-tetrahydroxypiperazine is subjected to a reaction for 5-10 min to obtain the 1, 4-diformyl-2, 3, 5, 6-tetrahydroxypiperazine. The acceleration of acoustic resonance is 196-980 m / s < 2 >, and the alkali liquor is selected from a sodium hydroxide aqueous solution, a potassium hydroxide aqueous solution or triethylamine. According to the present invention, the alkali-catalyzed aldehyde amine condensation reaction is achieved by using acoustic resonance reinforcement, the 1, 4-diformyl-2, 3, 5, 6-tetrahydroxypiperazine is rapidly and efficiently synthesized, the reaction time is substantially shortened, the product yield is improved, and the method has broad industrial application prospects.

The present application relates to 2-formylquinoline carboxamide compounds and medical uses thereof, the structure is shown as formula (I). The present application also relates to the preparation method of the compounds, pharmaceutical compositions and the use thereof as FGFR4 inhibitors in the treatment of cancer.

The present invention discloses an NH2-UiO-66 / PyCD-COF heterojunction photocatalyst and its preparation method and application. The preparation method includes: S1, dissolving zirconium chloride to obtain solution A; dissolving 2-aminoterephthalic acid to obtain solution B; S2, mixing and stirring, and reacting at 120-125 °C for 16-18 h to obtain NH2-UiO-66; S3, adding NH2-UiO-66, 1,3,6,8-tetrakis(4-formylphenyl)pyrene, and 2-chloro-1,4-phenylenediamine into an ortho-dichlorobenzene / n-butanol solution containing acetic acid, ultrasonic mixing in a Pyrex tube, freeze-degassing, and then vacuum-sealing; S4, reacting at 120 °C-130 °C for 3-5 days to obtain the NH2-UiO-66 / PyCD-COF heterojunction photocatalyst. The process of the present invention is simple and highly operable, and has excellent photocatalytic hydrogen production performance.

The present invention discloses a method for synthesizing 1,2-diketone compounds through surface coupling reaction. The steps are as follows: performing cyclic argon etching-annealing treatment on the Au(111) surface to obtain a clean Au(111) surface; depositing 1,3,5-tris(p-formylphenyl)benzene molecules and iron atoms onto the clean Au(111) surface successively to obtain a metal substrate with 1,3,5-tris(p-formylphenyl)benzene molecules and iron atoms; annealing the metal substrate. The present invention synthesizes 1,2-diketone compounds through surface coupling reaction, and the yield reaches 87.4%. Compared with the coupling reaction in traditional solution, the yield of 1,2-diketone compounds is significantly improved, and no by-products are generated. The synthesized 1,2-diketone compounds, as an important raw material for organic synthesis, can be widely applied to the synthesis and preparation fields such as medicine, chemical engineering, and polymer materials.

The invention relates to the technical field of medicine and chemical industry, and discloses an artemisinin C-16-bit derivative and a preparation method and application thereof, the structural general formula of the artemisinin C-16-bit derivative is as shown in formula (1): # imgabs0 #, R1 is one of 4-(tert-butyl) benzenesulfonyl, 4-chlorobenzenesulfonyl, 4-fluorobenzenesulfonyl, 4-(trifluoromethyl) benzenesulfonyl, 4-methyl benzoyl and cyclopropyl formyl; and n is 1 or 2. According to the artemisinin C-16 site derivative disclosed by the invention, a specific aryl ester group is introduced to the C-16 site, so that the molecular polarity and the pharmacokinetic property are optimized, and the anti-tumor activity is improved. The artemisinin C-16-bit derivative disclosed by the invention provides a new strategy for chemical research and development of novel artemisinin derivatives and cancer treatment.