92 Penicillium simplicissimumの生産する殺虫性インドールアルカロイドOkaramines(口頭発表の部)

概要

論文の詳細を見る
During the course of an investigation into insecticides produced by microorganisms, we got a soil isolate of Penicillium simplicissimum AK-40. This strain, when grown on okara (the insoluble residue of whole soybeans), showed strong activity to silkworms upon oral administration. We also succeeded in the isolation of novel insecticidal compounds named okaramines A (1), C_<32>H_<32>N_4O_3, and B(2), C_<33>H_<34>N_4O_5. Acetylation of 1 gave acetylokaramine A (3), whose structure was determined by an X-ray analysis. 1 is a new heptacyclic compound containing a hexahydropyrroloindole and dihydroazocinoindole, which are linked to form an additional diketopiperazine ring. The structure of 2 was elucidated by analyses of ^<13>C-, ^1H- and 2D-NMR spectra. Since we had an interest in the unique structures of okaramines, we tried to find if okaramines or similar compounds were produced by other strains. P. cimplicissimum AHU 8402 was shown to produce okaramine C (5), C_<32>H_<36>N_4O_3, together with 1 and 2. 2 was the most active among okaramines and their derivatives. 5 showed almost the same activity as 1. Despentenylokaramine A (4) had no activity. These data strongly suggest that an azetidine ring in 2 and an isoprene side chain at N^8 in 1 played an essential role in expressing the activity and that an azocine ring in 1 and 2 were unnecessary to exhibit the activity.
天然有機化合物討論会の論文
1991-09-07