Pictet-Spengler reaction of L-tryptophan methyl ester (9) and 6-methoxy-L-tryptophan methyl ester (40) with isovaleraldehyde (10) in methylene chloride in the presence of trifluoroacetic acid gave the cis-tetrahydro-β-carboline (11, 41) as the major isomer. The condensation of 11 and 41 with N-benzyloxycarbonyl-L-proline followed by deprotection gave the cis-cis- pentacycles (27, 44) which contain the parent ring system of fumitremorgins. The trans-cis ...