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Facile Synthesis of Pyrrolyl 4-Quinolinone Alkaloid Quinolactacide by 9-AJ-Catalyzed Tandem Acyl Transfer-Cyclization of o-Alkynoylaniline Derivatives.

ABSTRACT: The synthesis of pyrrolyl 4-quinolinone alkaloid, quinolactacide, and its analogues was successfully achieved using 9-azajulolidine (9-AJ)-catalyzed tandem acyl transfer-regioselective cyclization of N,N-diacyl-o-alkynoylaniline derivatives. In addition, this organocatalytic reaction was successfully utilized for the synthesis of a variety of 3-acyl-4-quinolinones in moderate-to-good yields. Mechanistic studies, including a time course nuclear magnetic resonance (NMR) experiment, indicated that the 1,4-addition of 9-AJ to an ynone system can be considered to be the rate-determining step in this quinolinone synthesis.

SUBMITTER: Saito K

PROVIDER: S-EPMC6641763 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Facile Synthesis of Pyrrolyl 4-Quinolinone Alkaloid Quinolactacide by 9-AJ-Catalyzed Tandem Acyl Transfer-Cyclization of o-Alkynoylaniline Derivatives.

Saito Koya K Yoshida Masahito M Uekusa Hidehiro H Doi Takayuki T

ACS omega 20170809 8

The synthesis of pyrrolyl 4-quinolinone alkaloid, quinolactacide, and its analogues was successfully achieved using 9-azajulolidine (9-AJ)-catalyzed tandem acyl transfer-regioselective cyclization of N,N-diacyl-o-alkynoylaniline derivatives. In addition, this organocatalytic reaction was successfully utilized for the synthesis of a variety of 3-acyl-4-quinolinones in moderate-to-good yields. Mechanistic studies, including a time course nuclear magnetic resonance (NMR) experi ...[more]

PMID: 31457730

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