Tropolone-Bearing Sesquiterpenes from <i>Juniperus chinensis</i>: Structures, Photochemistry and Bioactivity
Jae Sung Park, Keebeom Ko, Seong-Hwan Kim, Jae Kyun Lee, Jin‐Soo Park, Keunwan Park, Mi Ri Kim, Kyungsu Kang, Dong‐Chan Oh, Sun Yeou Kim, Silvia Yumnam, Hak Cheol Kwon, Jongheon Shin
Abstract
The tropolone-bearing sesquiterpenes juniperone A (1) and norjuniperone A (2) were isolated from the folk medicinal plant Juniperus chinensis, and their structures were determined by a combination of spectroscopic and crystallographic methods. Photojuniperones A1 (3) and A2 (4), bearing bicyclo[3,2,0]heptadienones derived from tropolone, were photochemically produced and structurally identified by spectroscopic methods. Predicted by the machine learning-based assay, 1 significantly inhibited the action of tyrosinase. The new compounds also inhibited lipid accumulation and enhanced the extracellular glycerol excretion.