Total Synthesis of Jerangolid D

Aliphatic C−H to C−C Conversion: Synthesis of (−)-Cameroonan-7α-ol

“…The synthesis commenced with a three step sequence of LiAlH 4 reduction, tosylation and nucleophilic displacement of (+)- 3 to provide the known nitrile 4 8. Homologation to the β-ketoester 1 was accomplished via Blaise reaction9 of the nitrile 4 with BrCH 2 CO 2 Et. We found that reproducibly high yields in this reaction could be achieved using activated Zn o metal10 and in situ activation with a catalytic amount of TFA 11.…”

Design, Synthesis and Anti-proliferative Activity of Novel 5,6-Dihydro-6-alkyl-2-pyrone Analogues

“…以化合物 2 为起始原料, 图式 脱苄基反应, 尝试了 Pd/C 加氢 [17,18] , 发现化合物 6 双键易被还原, 且产率较低. 于是分别筛选了无水三氯 化铁 [19] 和四氯化钛等路易斯酸催化脱苄基. 结果发现 用四氯化钛 [20,21] 催化搅拌过夜, 可以得到目标化合物.…”

Application of cyclic phosphonamide reagents in the total synthesis of natural products and biologically active molecules

“…Deprotection of TBS ether 197 with TBAF provided alcohol 194 which was then transformed into known phenyltetrazole (PT) sulfone 195 [142–143] through Mitsunobu reaction with 1-phenyltetrazole-5-thiol (PTSH), followed by oxidation of the intermediate sulfide. Coupling of the lactone building block in form of aldehyde 196 with the fully elaborated PT-sulfone 195 provided the corresponding olefin with the correct double-bond geometry in moderate yield and excellent selectivity ( E / Z > 25:1).…”

“…Coupling of the lactone building block in form of aldehyde 196 with the fully elaborated PT-sulfone 195 provided the corresponding olefin with the correct double-bond geometry in moderate yield and excellent selectivity ( E / Z > 25:1). Lastly, cleavage of the TBS ether under mild acidic conditions afforded jerangolid A ( 22 ) [27,143–144]. …”