trans-(±)-2-(4-Methoxyphenyl)-4-oxo-2,3,4,5-tetrahydro-1,5-benzothiazepin-3-yl Acetate

Abstract

The title compound, CI8H17NO4S , is a diltiazem-related compound. The molecular packing is predominantly stabilized by hydrogen bonding; amide groups hydrogen bond with adjacent molecules to form centrosymmetric dimers. The seven-membered ring is distorted, showing a twist-boat conformation. The benzene ring is planar but the methoxyphenyl ring deviates significantly from planarity. The relative configuration of the methoxyphenyl and acetoxy groups is gauche. CommentThe title compound, (I), is a drug intermediate in the synthesis of diltiazem, (II), an enantiomerically pure

Crystal structure of N-nitroso-2,3,4,5-tetrahydro-2,2,4-trimethyl-1,5- benzothiazepine, C12H16N2OS

“…This deviation from -34.4° [6] is attributed to the presence of sulfur atom, the bond angle around which deviates from the ideal tetrahedral angle of 109°. This conformation is in contrast to the twist boat conformation observed in similar molecules [7][8][9][10]. The sp 2 and sp 3 hybridized states for C10 and CI, respectively cause the difference in the S-C bond lengths in the title molecule.…”

cis-(±)-3-Acetoxy-2-(4-methoxyphenyl)-4-oxo-2,3,4,5-tetrahydro-1,5-benzothiazepine 1-Oxide

“…Atoms C(2) and C(3) lie above, and atoms C(23) and N(25) below this plane. The values of the torsion angles of (I) indicate a twist-boat conformation (Hendrickson, 1961) and are similar to those of both compound (II) and the diltiazem drug intermediate trans-(+)-2-(4-methoxyphenyl)-4-oxo-2,3,4,5-tetrahydro-1,5-benzothiazepin-3-yl acetate, (III) (Kumaradhas, Nirmala & Ravikumar, 1995). The methoxyphenyl and acetoxy groups on atoms C(9) and C(18), respectively, are cis oriented with respect to each other, as indicated by the torsion angle C(10)--C(9)---C(18)--O(19) of 40.4(17) °, and the dihedral angle between the methoxyphenyl group and the seven-membered ring is 71.1 (1)°.…”

Crystal and Molecular Structure of cis-(+)-3-Acetoxy-2-(4-methoxyphenyl)-4-oxo-2,3,4,5-tetrahydro-1,5-benzothiazepine-1-oxide

“…5 A similar type of confirmation has also been noticed in other analogous structures. [1][2][3][4] As expected, the benzene ring is planar and the methoxyphenyl group is significantly deviated from planarity. The methoxyphenyl and acetoxy groups at C(9) and C(18) are cis oriented with respect to one another, as indicated by the torsion angle .…”