Synthesis and monoamine oxidase B substrate properties of 1-methyl-4-heteroaryl-1,2,3,6-tetrahydropyridines.

Six analogues of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine [MPTP, (1)] bearing various heteroaryl groups at C-4 were synthesized and examined for their monoamine oxidase B substrate properties. The C-4 substituents include the 1-ethylpyrrol-2-yl, 1-propylpyrrol-2-yl, 1-isopropylpyrrol-2-yl, 1-cyclopropylpyrrol-2-yl, 3-ethylfuran-2-yl and 3-ethylthien-2-yl groups. The results provide information concerning steric and polar interactions between the C-4 substituent and the active site of MAO-B that are transmitted to the position of oxidation at C-6 of the tetrahydropyridinyl moiety.