Compound of the formula
wherein R, and R2 are each independently -H or lower alkoxy; R3 and R4 are each independently lower alkyl; and Rs and R6 are each -OCH3 or together form -OCH2O-or -OCH2CH2O-, and pharmaceutically acceptable acid addition salts thereof are disclosed as calcium channel blockers useful for treating cardiovascular disorders, including angina, hypertension and congestive heart failure.
The chemoselective S(N)2' reaction of a variety of primary nitroalkanes to dialkyl 2-(bromomethyl)fumarates can be efficiently performed under cetyltrimethylammonium hydroxide (CTAOH) catalysis. The alpha, beta-unsaturated esters were obtained in satisfactory to good yields with the complete retention of the nitro group. (C) 2009 Elsevier Ltd. All rights reserved.
US4613606A
申请人:——
公开号:US4613606A
公开(公告)日:1986-09-23
US4681889A
申请人:——
公开号:US4681889A
公开(公告)日:1987-07-21
SYNTHESIS OF MACROCYCLIC LACTONES APPLYING INTRAMOLECULAR 1,3-DIPOLAR CYCLOADDITION: SYNTHESIS OF (±)-A26771B
intramolecular 1,3-dipolar cycloaddition of the nitrile oxides derived from ω-nitroalkyl acrylates gave isoxazoline fused macrocycliclactones. The direction of 1,3-dipolar cycloaddition is strongly affected by the ring size of forming lactones. Utilizing this method, total synthesis of (±)-A26771B was achieved.