Isolation of Fluorescent Benzoxazines with Neuroprotective Activity from the Olive Weevil Pimelocerus perforatus

Abstract

The weevil Pimelocerus perforatus poses a serious pest problem for olive cultivation in Japan. Two new racemic fluorescent benzoxazines, designated as pimeforazine A ((±)-1) and pimeforazine B ((±)-2), were successfully isolated from P. perforatus. Their structures, including the absolute configurations of their resolved enantiomers, were determined using spectroscopic methods, single-crystal X-ray diffraction, and electronic circular dichroism calculations. The neuroprotective activity of the isolated compounds was evaluated against hydrogen peroxide-induced cellular damage in SH-SY5Y human neuroblastoma cells. Compounds (±)-1 and (±)-2 exhibited neuroprotective effects.

A micelle-mediated approach enables facile access to bridged oxabicyclo[n.3.1]alkene scaffolds

“…n .1] scaffolds represent a unique framework embedded in several bioactive natural products that structurally range from terpenes to alkaloids to steroids. 1 Some of the bioactive natural products that harbor oxabicyclo[3.3.1]nonenes and dioxabicyclo[3.3.1]nonenes as a core structural motif include cannabinoids, 2 (+)-hostmanin A, 3 murrafoline A, 4 pimeforazine A, 5 ephedrannin B, 6 etc. (Fig.…”