A novel synthesis of s-triazoloazines fused at the N2C3 bond of the triazole ring

Design, synthesis, and structure-activity relationship studies of novel fused heterocycles-linked triazoles with good activity and water solubility

Triazoles with fused-heterocycle nuclei were designed and evaluated for their in vitro activity on the basis of the binding mode of albaconazole using molecular docking, along with SAR of antifungal triazoles. Tetrahydro-[1,2,4]triazolo[1,5-a]pyrazine and tetrahydro-thiazolo[5,4-c]pyridine nuclei were preferable to the other four fused-heterocycle nuclei investigated. Potent in vitro activity, broad spectrum and better water solubility were attained when triazoles containing nitrogen aromatic heterocycles were attached to these two nuclei. The most potent compounds 27aa and 45x, with low hERG inhibition and hepatocyte toxicity, both exhibited excellent activity against Candida, Cryptococcus, and Aspergillus spp., as well as selected fluconazole-resistant strains. A high water-soluble compound 58 (the disulfate salt of 45x) displayed unsatisfactory in vivo activity because of its poor PK profiles. Mice infected with C.alb. SC5314 and C.alb. 103 (fluconazole-resistant strain) and administered with 27aa displayed significantly improved survival rates. 27aa also showed favorable pharmacokinetic (PK) profiles.

Design, synthesis, and biological evaluation of triazolopiperazine-based β-amino amides as potent, orally active dipeptidyl peptidase IV (DPP-4) inhibitors

Various beta-amino amides containing triazolopiperazine heterocycles have been prepared and evaluated as potent, selective, orally active dipeptidyl peptidase IV (DPP-4) inhibitors. These compounds display excellent oral bioavailability and good overall pharmacokinetic profiles in preclinical species. Moreover, in vivo efficacy in an oral glucose tolerance test in lean mice is demonstrated.

Synthesis of eosinophil infiltration inhibitors with antihistaminic activity

A series of [1, 2, 4]triazolo[1, 5-b]pyridazines (5) and imidazo[1, 2-b]pyridazines (6) having cyclic amines was synthesized and evaluated for antihistaminic activity and inhibitory effect on eosinophil infiltration. When a piperidine or a piperazine containing a benzhydryl group and a suitable spacer was incorporated at the 6-position, the fused pyridazines were found to exhibit both antihistaminic activity and an inhibitory effect on eosinophil chemotaxis. Above all, 6a showed potent antihistaminic activity, but little blockade of central H(1) receptors in contrast with its complete blockade of peripheral H(1) receptors as determined by an ex vivo binding assay. Furthermore, 6a inhibited eosinophil infiltration of the skin caused by a topical antigen challenge in sensitized guinea pigs, while an antihistamine terfenadine was not effective. After the pharmacokinetic study, 6a was found to be rapidly hydrolyzed to 6o, which was also orally active. Compound 6o, 2-[6-[[3-[4-(diphenylmethoxy)piperidino]propyl]amino]imidazo[1, 2-b]pyridazin-2-yl]-2-methylpropionic acid dihydrate (TAK-427), having both antihistaminic and antiinflammatory activity, is currently undergoing clinical trials as a therapeutic agent for atopic dermatitis and allergic rhinitis.