Staurosporine aglycone, synthesis

The cyclized products 393 can be prepared by the intramolecular coupling of diphenyl ether or diphenylamine(333,334]. The reaction has been applied to the synthesis of an alkaloid 394[335]. The intramolecular coupling of benzoyl-A-methylindole affords 5-methyl-5,10-dihydroindenol[l,2-b]indol-10-one (395) in 60% yield in AcOH[336]. Staurosporine aglycone (396) was prepared by the intramolecular coupling of an indole ring[337]. 

The Michael addition of the carbanions derived from esters to nitroalkenes followed by reductive cycLizadon has been used extensively for the preparation of pyrrondin-3-ones fEq 1076 This strategy is used for synthesis of the carbaaole alkaloid staurosporine aglycon CK-352c ... 

Oxidative homocoupling of aromatic and heteroaromatic rings proceeds with Pd(OAc)2 in AcOH. Biphenyl (165) is prepared by the oxidative coupling of benzene [104,105], The reaction is accelerated by the addition of perchloric acid. Biphenyl-tetracarboxylic acid (169), used for polyimide synthesis, is produced from dimethyl phthalate (168) commercially [106], Intramolecular coupling of the indole rings 170 is useful for the synthesis of staurosporine aglycone 171 [107]. 

Synthetic studies on indolocarbazoles Total synthesis cf staurosporine aglycon... 

Synthesis ofpyrrolidin-2-ones and staurosporine aglycon (K-252c) by intermolecular Michael reaction... 

Rajeshwaran GG, Mohanakrishnan AK. S3mthetic studies on indolocarbazoles Total synthesis of staurosporine aglycon. Qrg. Lett. 2011 13 (6) 1418-1421. 

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