98600-34-1Relevant articles and documents
Total synthesis of indiacen A using a practical one-pot reaction: Promoted by a key waste product, and its utility in natural products synthesis
Wang, Lihua,Lei, Ting,Wang, Fusheng,Jiang, Shizhi,Yan, Guiyang
, (2021)
Trialkylammonium salt, recognized as a waste product in the Heck reaction, was found to act as a key catalyst in the practical one-pot Heck-dehydration reaction. A concise synthesis of indiacen A was accomplished in 92% overall yield using a protecting-gr
Pd(II)-Catalyzed Transient Directing Group-Assisted Regioselective Diverse C4-H Functionalizations of Indoles
Dash, Om Prakash,Dey, Arnab,Pal, Kuntal,Singh, Anurag,Volla, Chandra M. R.
, p. 1941 - 1946 (2022/03/27)
The development of a rational strategy for achieving site-selective C4-H halogenation of indoles is an appealing yet challenging task. Herein, we disclose a Pd(II)-catalyzed transient directing group (TDG)-assisted methodology for realizing C4 chlorination/bromination of indoles employing glycine as the TDG and NFSI as a bystanding oxidant. The use of inexpensive and commercially available CuX2as the halide source is the key highlight of this protocol. Furthermore, the TDG methodology was also extended to accessing C4 acetoxylated indoles employing acetic acid as the acetate source and 1-fluoro-2,4,6-trimethylpyridinium triflate as the oxidant.
Asymmetric Total Synthesis of Sarpagine and Koumine Alkaloids
He, Ling,Jiang, Yan,Qiao, Zhen,Qiu, Hanyue,Su, Xiaojiao,Tan, Qiuyuan,Yang, Jiaojiao,Yang, Zhao,Zhang, Min,Zhou, Wenqiang
supporting information, p. 13105 - 13111 (2021/05/10)
We report here a concise, collective, and asymmetric total synthesis of sarpagine alkaloids and biogenetically related koumine alkaloids, which structurally feature a rigid cage scaffold, with L-tryptophan as the starting material. Two key bridged skeleton-forming reactions, namely tandem sequential oxidative cyclopropanol ring-opening cyclization and ketone α-allenylation, ensure concurrent assembly of the caged sarpagine scaffold and installation of requisite derivative handles. With a common caged intermediate as the branch point, by taking advantage of ketone and allene groups therein, total synthesis of five sarpagine alkaloids (affinisine, normacusine B, trinervine, Na-methyl-16-epipericyclivine, and vellosimine) with various substituents and three koumine alkaloids (koumine, koumimine, and N-demethylkoumine) with more complex cage scaffolds has been accomplished.