ammosamide-b and pyrroloquinoline

Bromodomain-containing protein 4 (BRD4), which is a member of the bromodomain and extra-terminal domain (BET) family, plays an important role in the regulation of gene expression as the "reader" of epigenetic regulation. BRD4 has become a promising target to treat cancer, because the up-regulation of BRD4 expression is closely associated with the occurrence and development of various cancers. At present, several BRD4 inhibitors are in clinical trials for cancer therapy, but no BRD4 inhibitors are on the market. Here, we designed and synthesized a series of compounds bearing pyrrolo[4,3,2-de]quinolin-2(1H)-one scaffold through structural modification of natural products ammosamide B, which is a natural pyrroloquinoline derivative reported for its potential antitumor activity. All target compounds were evaluated for their BRD4 BD1 inhibition activities via the protein thermal shift assays or AlphaSceen assay. The representative compound 49 showed potent activity (IC

Topics: Amides; Epigenesis, Genetic; Heterocyclic Compounds, 3-Ring; Nuclear Proteins; Pyrroles; Quinolines; Structure-Activity Relationship

A novel annulation reaction of 3-acylmethylidene oxindoles with Huisgen zwitterions is unveiled that leads to an unprecedented synthetic method for complex pyrrolo[4,3,2-de]quinolinones and marine alkaloids ammosamides A-C. This method features simplicity, high efficiency, and broad substrate scope and is accordingly anticipated to significantly facilitate the preparation and bioassay of the relevant pyrroloquinoline alkaloids and their analogues.

Topics: Alkaloids; Amides; Biological Products; Heterocyclic Compounds, 3-Ring; Indoles; Marine Biology; Molecular Structure; Oxindoles; Pyrroles; Quinolines; Quinolones; Structure-Activity Relationship

A total synthesis of ammosamide B (2), a member of the pyrroloquinoline alkaloid family isolated from marine Streptomyces, is described. The characteristic core tricyclic structure of 2 was constructed using a novel, tandem Friedel-Crafts reaction sequence to transform the symmetric tetra-amino substituted benzene derivative 7 into the tricyclic pyrroloquinoline product 8, which serves as an important intermediate in the route to the synthesis of the target natural product.

Topics: Amides; Heterocyclic Compounds, 3-Ring; Molecular Structure; Pyrroles; Quinolines