Synthetic studies on flavone derivatives. XIV. Synthesis of 2',4',5'-trioxygenated flavones.
作者:MUNEKAZU IINUMA、KIYOSHI IWASHIMA、SHIN MATSUURA
DOI:10.1248/cpb.32.4935
日期:——
Seven naturally occurring flavones oxygenated at C-2', C-4' and C-5' in ring B were synthesized, together with their isomers, to confirm the proposed structures. The synthesized flavones 1, 2, 3a, 5, 7 and 8 were identical with the corresponding natural flavones, but 4a was not. The spectral properties of these flavones are discussed.
Total Synthesis and Structure Revision of (−)-Siphonodictyal B and Its Biomimetic Conversion into (+)-Liphagal
作者:Adrian W. Markwell-Heys、Kevin K. W. Kuan、Jonathan H. George
DOI:10.1021/acs.orglett.5b01973
日期:2015.9.4
reassigned on the basis of the total synthesis of both possible C-8 epimers. The revised structure of siphonodictyal B was converted into liphagal by acid catalyzed rearrangement of a proposed epoxide intermediate. This biomimetic cascade features a succession of four distinct reactions (epoxidation, o-quinone methide formation, ringexpansion, and benzofuran formation) that occur in a one-pot operation
Divergent Synthesis of Marine Natural Products Siphonodictyal B, Corallidictyals C/D, and Liphagal Based on the Early Presence of an Aldehyde Group Instead of a Late-Stage Introduction
作者:Jun-Li Wang、Hui-Jing Li、Yan-Chao Wu
DOI:10.1021/acs.joc.8b00989
日期:2018.8.3
iodobenzaldehyde, without touching the aromatic aldehyde group, facilitated a divergent and expeditious access to bioactive marine naturalproducts siphonodictyal B, corallidictyals C/D, and liphagal based on the early presence of an aldehyde group instead of a late-stage introduction.