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Functionalization of 4-bromobenzo[c][2,7]naphthyridine via regioselective direct ring metalation. A novel approach to analogues of pyridoacridine alkaloids.

ABSTRACT: Readily available 4-bromobenzo[c][2,7]naphthyridine undergoes regioselective direct ring metalation at C-5 with TMPMgCl?LiCl at -40 °C. Quenching with various electrophiles gives a broad range of 5-substituted products, which are building blocks for the synthesis of heterocyclic natural products and analogues thereof. In combination with a Parham-type cyclization a novel approach to pyrido[4,3,2-mn]acridones has been worked out.

SUBMITTER: Melzer BC

PROVIDER: S-EPMC6774065 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Functionalization of 4-bromobenzo[c][2,7]naphthyridine via regioselective direct ring metalation. A novel approach to analogues of pyridoacridine alkaloids.

Melzer Benedikt C BC Plodek Alois A Bracher Franz F

Beilstein journal of organic chemistry 20190926

Readily available 4-bromobenzo[c][2,7]naphthyridine undergoes regioselective direct ring metalation at C-5 with TMPMgCl∙LiCl at -40 °C. Quenching with various electrophiles gives a broad range of 5-substituted products, which are building blocks for the synthesis of heterocyclic natural products and analogues thereof. In combination with a Parham-type cyclization a novel approach to pyrido[4,3,2-mn]acridones has been worked out. ...[more]

PMID: 31598182

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