1,5-Benzoxathiepin derivatives. III. Optical resolution of methyl (+/-)-cis-3-hydroxy-4-[3-(4-phenyl-1-piperazinyl)propyl]-3,4-dihydro- 2H-1,5-benzoxathiepin-4-carboxylate hydrochloride ((+/-)-CV-5197) with selective 5-hydroxytryptamine2(5-HT2)-antagonistic activity.
The selective 5-HT2-receptor antagonist, methyl (+/-)-cis-3-hydroxy-4-[3-(4-phenyl-1-piperazinyl)propyl]-3,4-dihydro-2H- 1,5-benzoxathiepin-4-carboxylate hydrochloride ((+/-)-CV-5197) was resolved in high optical purity using (R)-(-)- and (S)-(+)-1,1'-binaphthyl-2,2'-diyl hydrogen phosphates ((R)-(-)- and (S)-(+)-BNP). The absolute configuration of (+)-CV-5197 was determined to be 3S,4R by X-ray crystallographic analysis. In the binding assay, it was demonstrated that (+)-CV-5197 was a more active isomer (IC50 = 23 nM +/- 6.3) for 5-HT2 receptor binding than the (-)-enantiomer (IC50 = 1600 nM +/- 82). (+)-CV-5197 completely inhibited the 5-HT-induced contraction of the isolated pig coronary artery at a concentration of 3 x 10(-7) M, whereas (-)-CV-5197 showed little antagonistic activity, even at 3 x 10(-4) M. Thus, the agreement between the results of the binding assays and the biological activities for the 3S,4R enantiomer of CV-5197 suggests that its physiological activity is probably exerted through 5-HT2-receptor antagonism.
Kori
M
M
Chemistry Research Laboratories, Takeda Chemical Industries, Ltd., Osaka, Japan.
Kamiya
K
K
Kurihara
E
E
Sugihara
H
H
D000818:Animals; D066298:In Vitro Techniques; D010879:Piperazines / Q000737:chemistry / Q000494:pharmacology*; D011985:Receptors, Serotonin / Q000378:metabolism; D012702:Serotonin Antagonists / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D013552:Swine
D010879:Piperazines; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; C070674:CV 5197