Total Syntheses of Proposed (±)-Trichodermatides B and C.
Total syntheses of putative (±)-trichodermatides B and C are described. These efficient syntheses feature theoxa-[3 + 3] annulation strategy, leading to B and C along with their respective C2-epimers. However, these synthetic samples are spectroscopically very different from the natural products. DFT calculations of C13 chemical shifts are conducted and the predicted values are in good agreement with those of synthetic samples, thereby questioning in the accuracy of structural assignments of trichodermatides B and C.
School of Pharmaceutical Science and Technology, Key Laboratory for Modern Drug Delivery and High-Efficiency, Tianjin University, Tianjin, 300072 P. R. China.
Qian
Q
Li
Yan-Shuang
YS
Xu
Gregory A
GA
Ellis
Timothy S
TS
Bugni
Yu
Y
Tang
Richard P
RP
Hsung
DFT calculations; Davis’ oxaziridine; Trichodermatides; biosynthesis; electrocyclic ring-opening; oxa-[3 + 3] annulation