I. N. Shishkina

Monoclinic form I of clopidogrel hydrogen sulfate from powder diffraction data

The asymmetric unit of the title compound, C16H17ClNO2S+·HSO4 −, (I) [systematic name: (+)-(S)-5-[(2-chlorophenyl)(methoxycarbonyl)methyl]-4,5,6,7-tetrahydrothieno[3,2-c]pyridin-5-ium hydrogen sulfate], contains two independent cations of clopidogrel and two independent hydrogensulfate anions. The two independent cations are of similar conformation; however, this differs from that observed in orthorhombic form (II) [Bousquet et al. (2003 ▶). US Patent No. 6 504 030]. The H—N—Cchiral—H fragment shows a trans conformation in both independent cations in (I) and a gauche conformation in (II). In (I), classical intermolecular N—H⋯O and O—H⋯O hydrogen bonds link two independent cations and two independent anions into an isolated cluster, in which two cations interact with one anion only via N—H⋯O hydrogen bonds. Weak intermolecular C—H⋯O hydrogen bonds further consolidate the crystal packing.

Synthesis of chiral 1,3-dihydroisobenzofurans (phthalans) containing functional substituents in the 1-position

Chiral 3-methyl-1,3-dihydroisobenzofurans (phthalans) having a carbonyl or α-hydroxybenzyl group in position 1 were synthesized by cyclization of the corresponding trimethyl[(S)-1-phenylethyl]ammonium iodides. The configuration of the chiral centers in the products was determined by X-ray analysis.

New chiral ligands: 1,4-diols prepared from (S)-1-phenylethanol

The stereochemistry of condensation of dilithiated 1-phenylethanol with various carbonyl compounds was investigated. In most cases the reaction proceeds nonstreoselectively, and only in the condensation with PhCOBu-t and 2,4-(MeO)2C6H3COPh only one of the diastereomeric diols prevailed. It was shown by XRD analysis that in the prevailing diastereomeric diol the newly formed chiral carbinol center possessed the same configuration as the initial alcohol. The synthesized diols form homochiral dimers in the crystal lattice.

Molecular and crystal structures of (S,S)-[o-(α-dimethylaminoethyl)phenyl]phenylarylcarbinols

AbstractThe crystal structures of (S,S)-o-(α-dimethylaminoethyl)phenyl]phenyl-2,4-dimethylphenyl-carbinol (I) and (S,S)-o-(α-dimethylaminoethyl)phenyl]phenyl-2,4,5-trimethylphenylcarbinol (II) are determined by X-ray diffraction. The molecular and crystal structures of I and II are similar. The crystal structures of I and II are compared based on the analysis of the geometric characteristics of the Vorono

Stereochemical Features of the Condensation of Lithiated (S)-N,N-Dimethyl-1-phenylethylamine with o-Methoxybenzophenones

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Effect of intramolecular interactions on circular dichroism of ortho-substituted 1-phenethylamines†

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Catalyzed asymmetric dialkylzinc addition to benzaldehyde in the presence of new chiral ligands — δ-(1-phenethyl)aminoalcohols

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Synthesis and configuration of (1S,3R)- and (1R,3R)-1-(3,4-dimethoxyphenyl)-1,3-dimethyl-1,3-dihydroisobenzofurans

2-Dirichlet packing polyhedra. The circular dichroism spectra of amino alcohols I and II revealed a strong positive Cotton effect in the region of 230 nm, which correlates with the S-configuration of the chiral carbinol center.