| abstract |
A process is disclosed for the preparation of disubstituted acetylene derivatives having retinoic acid like biological activity, wherein 6-ethynyl-chroman, 6-ethynyl-thio chroman and 6-ethynyl-1,2,3,4-tetrahydroquinoline derivatives of the formula shown below are reacted in the presence of catalysts with halogenated phenyl or heteroaryl derivatives of the formula shown below to provide the disubstituted acetylenes. n In the formulae the symbols have the following meanings, R₁, R₂, R₃, R₄ and R₅ are hydrogen or lower alkyl groups (of 1-6 carbons) where R₁, R₂, R₃, R₄ and R₅ may be identical or different from one another) X is S, O or NR′ where R′ is hydrogen or lower alkyl, Z represents hydrogen, or a metal ion capable of forming a salt with the ethynyl moiety of the molecule, X′ is a leaving group such as a halogeno group, A is phenyl, or heteroaryl such as pyridinyl, thienyl, furyl, pyridazinyl, pyrimidinyl, pyrazinyl, thiazolyl or oxazolyl, n is an intetger between 0 to 5, and B is H, -COOH or a pharmaceutically acceptable salt, ester or amide thereof, -CH₂OH or an ether or ester derivative, or -CHO or an acetal derivative, or -COR₁ or a ketal derivative where R₁ is an alkyl, cycloalkyl or alkenyl group containing 1 to 5 carbons. |