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Li J.-J., Shen H.-J. and Tan C.-H. have successfully defended their dissertations.

Li Jin-jie, Shen Hong-juan and Tan Ce-heng have successfully defended their dissertations and shall be conferred the doctor’s degree. Congratulations!

102.Isolation and Asymmetric Total Synthesis of Perforanoid A

Chao Lv , Xiaohui Yan , Qian Tu, Yingtong Di, Chunmao Yuan, Xin Fang, Yaacove Ben-David, Lei Xia, Jianxian Gong, Yuemao Shen,* Zhen Yang,* and Xiaojiang Hao*

Angew. Chem. Int. Ed. 2016, 55, 7539

• Highlighted in Org. Chem. Highlights 2017, March 6.

A novel limonoid, perforanoid A, was isolated, and an asymmetric total synthesis was achieved in 10 steps. The key steps are chiral tertiary aminonaphthol mediated enantioselective alkenylation of an aldehyde to an allylic alcohol, Pd-catalyzed coupling of the allylic alcohol with vinyl ether to form the γ-lactone ring, and cyclopentenone ring formation through a Rh-catalyzed Pauson–Khand reaction. Preliminary studies show that perforanoid A is cytotoxic towards HEL, K562, and CB3 tumor cell lines.

2016

101.Regio- and Stereoselective Syntheses of 7-Oxabicyclo[2.2.1]heptanes via a Gold(I)-Catalyzed Cycloisomerization of Alkynediols: Asymmetric Total Synthesis of Farnesiferol C

Yue-Qing Gu, Peng-Peng Zhang, Jun-Kai Fu, Song Liu, Yu Lan,* Jian-Xian Gong,* and Zhen Yang*

Adv. Synth. Catal. 2016, 358, 1392-1397

A highly regio- and stereoselective method to construct a broad range of 7-oxabicyclo[2.2.1]heptanes, which proceeds through a sequential reaction involving gold(I)-catalyzed cycloisomerization of alkynediols and sequential semi-pinacol-type 1,2-alkyl migration, was developed. The developed chemistry was applied to the asymmetric total synthesis of the natural product farnesiferol C.

100.Gold-Catalyzed Enantio- and Diastereoselective Syntheses of Left Fragments of Azadirachtin/Meliacarpin-Type Limonoids

Hang Shi, Ceheng Tan, Weibin Zhang, Zichun Zhang, Rong Long, Jianxian Gong, Tuoping Luo*, and Zhen Yang*

J. Org. Chem., 2016, 81, 751

Meliacarpin-type limonoids are an important class of organic insecticides. Their syntheses are challenging due to their chemical complexity. Here, we report the highly enantio- and diastereoselective synthesis of the left fragments of azadirachtin I and 1-cinnamoylmelianolone, being two important family members of meliacarpin-type limonoids, via pairwise palladium- and gold-catalyzed cascade reactions. Gold-catalyzed reactions of 1,7-diynes were performed as model studies, and the efficient construction of tetracyclic late-stage intermediates was achieved on the basis of this key transformation. Our unique route gave both of the left fragments in 23 steps from the commercially available chiral starting material (−)-carvone. This study significantly advances research on the synthesis of the meliacarpin-type limonoids.

Congratulations to Prof. Yang on winning The Excellent Talent Awards of Shenzhen

Congratulations to Prof. Yang on winning The Excellent Talent Awards of Shenzhen for 2015.