| abstract |
Title cpds. are of formula: (where R is H, one equiv. of a base, a cyclo(aliphatic, cycloaliphatic-aliphatic, aromatic or araliphatic group; A is -CH2-CH2- or =CH=CH-; R1, R2 are H or lower alkyl; R3 is (cyclo)aliphatic, cycloaliphatic-aliphatic, araliphatic; x is 0, 1 or 2) together with their 1,2-dihydro and -dehydro derivs. and their salts. (I) are prepd. conventionally, e.g. by reduction of the corresp. 3-oxo cpds. |