Spirochensilides A and B, Two New Rearranged Triterpenoids from Abies chensiensis

Abstract

Two new triterpenoids, spirochensilides A (1) and B (2) were isolated from Abies chensiensis. Comprehensive spectroscopic analysis revealed that 1 and 2 are the first example of triterpenoids possessing a unique 8,10-cyclo-9,10-seco and methyl-rearranged carbon skeleton. The single crystal X-ray diffraction analyses and computational methods allowed the absolute configuration assignments of the two compounds. A plausible biogenetic pathway of spirochensilide A (1) is also proposed.

Synthesis, in vitro cytotoxicity, ADME, and molecular docking studies of benzimidazole‐bearing furanone derivatives

“…[ 6,7 ] Many natural products containing furanone moiety (Figure 1) have received increasing attention because of their biological and pharmacological activities, such as antitumor, antimicrobial, antiviral, and anti‐HIV. [ 8–14 ] They have been shown to exhibit significant biological activities, [ 15–17 ] including antifungal, [ 13,18 ] antibacterial, [ 9 ] antiviral, [ 19,20 ] and anticancer. [ 21,22 ] In lieu of the above mentioned activities, the synthesis of different furanones, their derivatives, and their applications in the area of medicine have drawn considerable attention in recent years.…”

A New Metric for Evaluating DFT Calculated Proton and Carbon Chemical Shifts of Natural Products and Organic Compounds

“…Examining the spectra from supporting information of Ref. [13], the COSY spectrum could not be distinguished between the protons on C5 and C6 due to spectral crowding in this region. Additionally, in the HMBC the H7 to C14 correlation would be diagnostic but the observed cross peak at ~160-1.7 ppm does not help since both H6 and H7 have one of their protons at ~1.7 ppm.…”

“…Spirochensilide A (5) was isolated from Abies chensiensis. [13] The single crystal X-ray diffraction analyses confirmed the structure, but most importantly fully determined the absolute configuration as 3S,5R,8R,10S,13R,16R,17S,20R and 23S. A conformational search of 5 was undertaken with MacroModel, [12] which resulted in four conformations < 5 kcal/mol from the global minimum.…”

Triterpenoids

“…45 Spirochensilides A 132 and B 133 are rearranged lanostanes from Abies chensiensis. 46 The structure of spirochensilide A 132 was conrmed by X-ray analysis. Two groups of compounds, neoabieslactones G 134-K 138 and abiestrines K 139-M 142, have been reported from Abies faxoniana.…”