34 results about "Stereocenter" patented technology

A method of introducing a second stereogenic center into a tetrahydro-β-carboline have two stereogenic centers using a modified Pictet-Spengler reaction is disclosed. The method provides a desired cis- or trans-isomer in high yield and purity, and in short processes times.

This invention provides enantioenriched heterocyclic enaminone compounds with quaternary stereogenic centers and novel methods of preparing the compounds. Methods include the method for the preparation of a compound of formula (I):comprising treating a compound of formula (II):with a transition metal catalyst under alkylation conditions.

A method of introducing a second stereogenic center into a tetrahydro-β-carboline have two stereogenic centers using a modified Pictet-Spengler reaction is disclosed. The method provides a desired cis- or trans-isomer in high yield and purity, and in short processes times.

The present invention provides complex compounds reminiscent of natural products and libraries thereof, as well as methods for their production. The inventive compounds and libraries of compounds are reminiscent of natural products in that they contain one or more stereocenters, and a high density and diversity of functionality. In general, the inventive libraries are synthesized from diversifiable scaffold structures, which are synthesized from readily available or easily synthesizable template structures. In certain embodiments, the inventive compounds and libraries are generated from diversifiable scaffolds synthesized from a shikimic acid based epoxyol template. In other embodiments, the inventive compounds and libraries are generated from diversifiable scaffolds synthesized from the pyridine-based template isonicotinamide. The present invention also provides a novel ortho-nitrobenzyl photolinker and a method for its synthesis. Furthermore, the present invention provides methods and kits for determining one or more biological activities of members of the inventive libraries. Additionally, the present invention provides pharmaceutical compositions containing one or more library members.

A process for producing an enantiomerically enriched compound of Formula I:where the R-configuration, or S-configuration at the stereogenic center is marked with an *; by hydrogenating an enamide of formula III:in an organic solvent in the presence of a catalyst comprising a transition metal selected from rhodium or iridium, complexed to a chiral diphosphine ligand;Ar is optionally substituted phenyl;Z is OR1, SR1 or NR1R2; and P is R3, OR3 or NR3R4;R1 and R2 are selected from H, C1-8 alkyl, C5-12 cycloalkyl, aryl and aryl-C1-2-alkyl; or R1 and R2 together with the nitrogen atom form a C4-7-membered heterocyclic ring optionally fused with a 5- to 6-membered carbocyclic or heterocyclic ring; andR3 and R4 are selected from H, C1-8 alkyl, aryl, C5-12 cycloalkyl and aryl-C1-2-alkyl; or R3 and R4 together with the nitrogen atom form a C4-7-membered heterocyclic ring.

The present invention relates to a process of manufacturing compound having stereogenic centers from a mixture of E / Z isomers of unsaturated compounds having prochiral double bonds. The hydrogenation product has a specific desired configuration at the stereogenic centers. The process involves an asymmetric hydrogenation and an isomerization step. The process is very advantageous in that it forms the desired chiral product from a mixture of stereoisomers of the starting product in an efficient way.

Focused library synthesis and medicinal chemistry on an oxadiazole-isopropylamide core proteasome inhibitor provided the lead compound that strongly inhibits CT-L activity. Structure activity relationship studies indicate the amide moiety and two phenyl rings are sensitive toward synthetic modifications. Only para-substitution in the A-ring was important to maintain potent CT-L inhibitory activity. Hydrophobic residues in the A-ring's para-position and meta-pyridyl group at the B-ring significantly improved inhibition. The meta-pyridyl moiety improved cell permeability. The length of the aliphatic chain at the para position of the A-ring is critical with propyl yielding the most potent inhibitor, whereas shorter (i.e. ethyl, methyl or hydrogen) or longer (i.e. butyl, propyl and hexyl) chains demonstrating progressively less potency. Introduction of a stereogenic center next to the ether moiety (i.e. substitution of one of the hydrogens by methyl) demonstrated chiral discrimination in proteasome CT-L activity inhibition (the S-enantiomer was 35-40 fold more potent than the R-enantiomer).

Control or repellency of mosquitoes is accomplished by bringing the insects into contact with at least one of the compounds of the structure (I)whereinR is selected from —OH, ═O, —OC(O)R4, —OR6, —(OR6)2, wherein each R6 is independently selected from an alkyl group containing from 1 to 4 carbon atoms and R4 is a branched or straight chain, saturated or unsaturated hydrocarbyl group with zero to two double bonds and from 1 to 15 carbon atoms;X is O or CH2, with the proviso that when X is O R can only be ═O;each Z is independently selected from (CH) and (CH2);y is a numeral selected from 1 and 2;R1 is selected from H or a branched or straight chain, saturated or unsaturated hydrocarbyl group with zero to two double bonds and from 1 to 15 carbon atoms;R2 is selected from H and a branched or straight chain, saturated or unsaturated hydrocarbyl group with zero to three double bonds and from 1 to 15 carbon atoms;R3 is selected from the group consisting of H and a branched or straight chain, saturated or unsaturated hydrocarbyl group with zero to three double bonds and from 1 to 15 carbon atoms, —(CH2)nOH, —C(O)OR5, —CH2C(O)OR7, —CH2C(O)R8, —C(O)NR9R10, —CH2C(O)NR11R12 where each of R5, R7, R8, R9, R10, R11 and R12 is independently selected from H and a branched or straight chain, saturated or unsaturated hydrocarbyl group with zero to three double bonds and from 1 to 15 carbon atoms and n is an integer of from 1 to 12;the bond between the 2 and 3 positions in the ring structure may be a single or a double bond; andwherein the compounds of structure (I) contain from 11 to 20 total carbon atoms in the compounds, with the proviso that when R is ═O, X is CH2, Z is CH2, y is 1 R2 is H, and R3 is CH2C(O)OR7 then the total number of carbon atoms in the compounds of structure (I) is from 15 to 20 carbon atoms, and when X is O and R is ═O the total number of carbon atoms in the compounds of structure (I) is from 11 to 17 carbon atoms. The invention also includes optical isomers, diastereomers and enantiomers of the named structures. Thus, at all stereocenters where stereochemistry is not explicitly defined, all possible epimers are envisioned.

The present invention relates to asymmetric catalysts, including redox-reconfigurable asymmetric catalysts. Methods of producing compounds having one or more stereocenters using the asymmetric catalysts of the present invention are also disclosed.

The disclosure provides new and improved methods for the Pd-catalyzed asymmetric α-arylation of ester compounds, which produce the corresponding α-aryl moiety in high enantioselectivity (generally >90% ee). The present methods utilize a palladium catalyst supported by new (R)—H8-BINOL-derived monophosphine ligands. The method is applicable to a wide variety of aryl triflate substrates having variations in both electronic and steric properties. These aryl triflate substrates react with various α-alkyl (Z)- and / or (E)-0-trimethylsilyl ketene acetals in the presence of a Pd catalyst, (R)—H8-BINOL-derived monophosphine ligand, and a mild activator, for example, LiOAC, to provide the asymmetric α-arylation of ester compounds in high ee.

Provided are a C-5 alpha-stereocenter 4-nitro isoxazole alcohol compound with high enantioselectivity and a preparation method and application thereof. The structural formula is shown in the description, wherein R1 refers to Me, Et, Ph and thienyl, and R2 refers to Me and normal-butyl. By adopting the new method to synthesize the C-5 alpha-stereocenter 4-nitro isoxazole alcohol compound with the high enantioselectivity, the C-5 alpha-stereocenter 4-nitro isoxazole alcohol compound with the high enantioselectivity serves as an initiator to synthesize a fungicide pyrazol compound (CAS: 1845899-33-3) with a high yield through four synthesis steps, and the specific information is shown in the description. At present, this kind of method is not reported, and the new method has the advantages ofbeing applicable in common use, low in cost, reasonable in reaction path, simple in post-processing and efficient in preparation of the compound with high optical purity.

Disclosed herein is a single step catalytic process for the production of enantiomerically pure α-Aryloxy-α′-Azido / Alkoxy alcohols of formula (A). The invention, in particular discloses phenolytic kinetic resolution of racemic anti and syn azido / alkoxy epoxides to generate two stereocentres of high optical purities of formula (A).

The present invention relates to a process of manufacturing compound having stereogenic centers from a mixture of E / Z isomers of unsaturated compounds having prochiral double bonds. The hydrogenation product has a specific desired configuration at the stereogenic centers. The process involves two asymmetric hydrogenation steps. The process is very advantageous in that it forms the desired chiral product from a mixture of stereoisomers of the starting product in an efficient way.

2-(2,5-dioxopyrrolidin-1-yl)propanamide and 2-(2-oxopyrrolidin-1-yl)propanamide derivatives with R-configuration at the stereogenic center are disclosed, showing broad- spectrum protective activity in animal models of epileptic seizures, pain, depression and anxiety that are simultaneously devoid of undesirable sedative effects. Additionally, the disclosed derivatives have neuroprotective effects in the in vitro and in vivo studies.

Disclosed is a method for synthesizing a sitagliptin intermediate, the method comprising: in the presence of hydrogen and a transition metal catalyst having a chiral phosphine ligand, subjecting a compound of formula II to an asymmetric reductive amination with ammonia or ammonium salt in a proper organic solvent under the condition of adding an acidic additive to produce a compound of formula I, wherein, an R- or S-configuration of a stereocenter is represented by *; the compound of formula I of R configuration can be used to prepare sitagliptin, and a reaction formula is as follows: R1 and R2 are each independently selected from hydrogen, C1-C12 linear or branched alkyl, C3-C12 cycloalkyl, C2-C12 alkenyl, C2-C12 alkynyl and C7-C12 arylalkyl. The method has a high yield and a high ee % value, a mild reaction condition and a low production cost, and is simple to operate, convenient to purify, environmental friendly and suitable for industrial production.