Methyl 2-{[(6S*,7R*,8S*)-7-acetyl-8-(4-chlorophenyl)-4-cyano-6-hydroxy-1,6-dimethyl-5,6,7,8-tetrahydroisoquinolin-3-yl]sulfanyl}acetate

Abstract

In the title compound, C 23 H 23 ClN 2 O 4 S, the 4-chlorophenyl ring is inclined to the pyridine ring of the isoquinoline group by 71.86 (13) . In the crystal, molecules are linked by pairs of O-HÁ Á ÁO hydrogen bonds, forming inversion dimers, which stack along the b-axis direction. The methyl acetate group attached to the S atom is disordered over two sites in a 50:50 ratio, which appears to prevent close intermolecular contacts between the methyl groups.

Synthesis and Characterization of Novel Functionally Substituted Planar Pyrimidothienoisoquinolines and Nonplanar (3aR, 4S, 9aS)-pyrazolo[3,4-g]isoquinolines

“…The absolute configurations of the three chiral centers of this isomer are detected by studying the X-ray diffraction of the single crystal of compounds 3a – c . The previous studies confirmed 6 S , 7 R , and 8 S configurations for the three chiral centers of compounds 3a – c . − …”

“…According to the crystal structure data provided by Dyachenko et al . and Mague et al, , for compounds 3a – c , the cyclohexene ring presented in half chair conformation and both acetyl and hydroxyl groups were in the same direction. Hence, the condensation of the acetyl group of compound 6a with hydrazine derivatives may give the corresponding hydrazone intermediates A , which undergo intramolecular cycloaddition reaction according to the Felkin–Ahn model to give pyrazoloisoquinolines 11a , b rather than 12a , b .…”

“…Alkylation of 2a , b with methyl iodide, ethyl iodide, or methyl chloroacetate, by refluxing in ethanol containing the appropriate base, is reported to give the S -alkylated derivatives 3a – c (Scheme ).…”

“…Its interesting to note that since the alkylation process takes place far away from the chiral centers of 2a , b , the configuration of these centers is similar to that of their alkylated products, i.e., 6 S , 7 R , and 8 S . − …”

“…The acetyl group of compounds 2a , b may possess low or no activity toward some reagents such as hydrazine hydrate, thiosemicarbazide, or phenylhydrazine because of the steric hindrance caused by its neighboring groups and its formation of hydrogen bonding with the tert hydroxyl group wherein the two groups (COMe and OH) are in the same direction as the cyclohexene ring. − …”