Compounds of the formula
wherein:
R₁ is cyano or nitro;
R₂ and R₃ are independently hydrogen or lower alkyl; and
R₄ is alkyl; alkenyl; optionally substituted phenyl or phenyl lower alkyl; -(CH₂)mOR₂ or -(CH₂)mN(R₂)₂; wherein m is an integer of 1-5 and R₂ is as defined above;
or a pharmaceutically acceptable ester or acid addition salt thereof;
are smooth muscle relaxants, particularly useful in the treatment of hypertension.
Preparation and Intramolecular [2+2]-Photocycloaddition of 1,5-Dihydropyrrol-2-ones and 5,6-Dihydro-1<i>H</i>-pyridin-2-ones with C-, N-, and O-linked Alkenyl Side Chains at the 4-Position
作者:Dominik Albrecht、Birte Basler、Thorsten Bach
DOI:10.1021/jo7027129
日期:2008.3.1
ion include the use of dichloromethane as the solvent and an irradiation with a mercury low-pressure lamp (λ = 254 nm). Upon applying these conditions at ambient temperature, the corresponding intramolecular photocycloaddition products 28−37 were obtained in good yields (52−79%) and with perfect diastereoselectivity. The constitution and configuration of the products was elucidated by NMR-spectroscopy