New synthetic method for indole-2-carboxylate and its application to the total synthesis of duocarmycin SA.
The sequential coupling and cyclization reactions between aryl halides and methyl propiolate were investigated. The electron-withdrawing groups on the aromatic ring are essential for producing the methyl indole-2-carboxylate derivatives. On the other hand, the presence of an extra methyl propiolate and Pd(PPh3)4 were required to provide an efficient catalytic system for the cyclization reactions. This reaction was used for the total synthesis of duocarmycin SA.
Hiroya
Kou
K
Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba-ku, Sendai 980-8578, Japan. hiroya@mail.trains.tohoku.ac.jp
Matsumoto
Shigemitsu
S
Sakamoto
Takao
T
D003500:Cyclization; D000080890:Duocarmycins; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D011758:Pyrroles / Q000138:chemical synthesis
D000080890:Duocarmycins; D007211:Indoles; D011758:Pyrroles; C503382:indole-2-carboxylate; C066098:duocarmycin SA