Strategies to mitigate the bioactivation of 2-anilino-7-aryl-pyrrolo[2,1-f][1,2,4]triazines: identification of orally bioavailable, efficacious ALK inhibitors.

Chemical strategies to mitigate cytochrome P450-mediated bioactivation of novel 2,7-disubstituted pyrrolo[2,1-f][1,2,4]triazine ALK inhibitors are described along with synthesis and biological activity. Piperidine-derived analogues showing minimal microsomal reactive metabolite formation were discovered. Potent, selective, and metabolically stable ALK inhibitors from this class were identified, and an orally bioavailable compound (32) with antitumor efficacy in ALK-driven xenografts in mouse models was extensively characterized.

2,7-Pyrrolo[2,1-f][1,2,4]triazines as JAK2 inhibitors: modification of target structure to minimize reactive metabolite formation.

The JAK2/STAT pathway has important roles in hematopoiesis. With the discovery of the JAK2 V617F mutation and its presence in many patients with myeloproliferative neoplasms, research in the JAK2 inhibitor arena has dramatically increased. We report a novel series of potent JAK2 inhibitors containing a 2,7-pyrrolotriazine core.

2,7-Disubstituted-pyrrolotriazine kinase inhibitors with an unusually high degree of reactive metabolite formation.

There are numerous published studies establishing a link between reactive metabolite formation and toxicity of various drugs. Although the correlation between idiosyncratic reactions and reactive metabolite formation is not 1:1, the association between the two is such that many pharmaceutical companies now monitor for reactive metabolites as a standard part of drug candidate testing and selection. The most common method involves in vitro human microsomal incubations in the presence of a thiol trapping agent, such as glutathione (GSH), followed by LC/MS analysis.

2,7-disubstituted-pyrrolo[2,1-f][1,2,4]triazines: new variant of an old template and application to the discovery of anaplastic lymphoma kinase (ALK) inhibitors with in vivo antitumor activity.

A novel 2,7-disubstituted-pyrrolo[2,1-f][1,2,4]triazine scaffold has been designed as a new kinase inhibitor platform mimicking the bioactive conformation of the well-known diaminopyrimidine motif. The design, synthesis, and validation of this new pyrrolo[2,1-f][1,2,4]triazine scaffold will be described for inhibitors of anaplastic lymphoma kinase (ALK). Importantly, incorporation of appropriate potency and selectivity determinants has led to the discovery of several advanced leads that were orally efficacious in animal models of anaplastic large cell lymphoma (ALCL).

Synthesis and structure-activity relationships of novel pyrrolocarbazole lactam analogs as potent and cell-permeable inhibitors of poly(ADP-ribose)polymerase-1 (PARP-1).

A series of novel pyrrolocarbazole lactams was identified as potent PARP-1 inhibitors in vitro and in a PC12 cellular NAD(+) depletion assay. The SAR trends of substituents at the 3-position, as well as the effect of blocking the indole or lactam NH-groups of the template by methylation or formylation, are discussed in relation to molecular modeling studies.

Synthesis and structure-activity relationships of novel poly(ADP-ribose) polymerase-1 inhibitors.

A series of novel pyrrolocarbazoles was synthesized as potential PARP-1 inhibitors. Pyrrolocarbazole 1 was identified as a potent PARP-1 inhibitor (IC50 = 36 nM) from our internal database. Synthesis of analogs around this template with the aid of modeling studies led to the identification of the truncated imide 14.

1,2-Benzothiazine 1,1-dioxide alpha-ketoamide analogues as potent calpain I inhibitors.

A series of potent 1,2-benzothiazine 1,1-dioxide alpha-ketoamide inhibitors of calpain I is described.