Design, synthesis and transformation of some heteroannulated 3-aminopyridines—purine isosteres with exocyclic nitrogen atom

Trifluoromethyl Vinamidinium Salt as a Promising Precursor for Fused β-Trifluoromethyl Pyridines

An efficient chlorotrimethylsilane-promoted synthetic protocol for the preparation of functionalized fused β-trifluoromethyl pyridines by cyclization of electron-rich aminoheterocycles or substituted anilines with a trifluoromethyl vinamidinium salt was developed. The efficient and scalable approach for producing represented trifluoromethyl vinamidinium salt demonstrated huge prospects for further use. The structure specificities of the trifluoromethyl vinamidinium salt and their impact on the reaction progress were determined. The procedure's scope and alternative ways of the reaction were investigated. The possibility of increasing the reaction scale up to 50 g and further modification of obtained products was shown. A minilibrary of potential fragments for ¹⁹F NMR-based fragment-based drug discovery (FBDD) was synthesized.

Straightforward entry to pyrido[2,3-d]pyrimidine-2,4(1H,3H)-diones and their ADME properties

A straightforward synthesis of pyrido[2,3-d]pyrimidine-2,4(1H,3H)-diones was developed starting from 2-chloropyridine-3-carboxylic acid by esterification, nucleophilic aromatic substitution and amide formation in one step, and ring closure allowing their synthesis with two identical or two different group attached to nitrogen. The structural diversity of these [2,3-d]pyrimidine-2,4(1H,3H)-diones resulted in significant variation in the biopharmaceutical properties. This was reflected by the broad range in fasted state simulated intestinal fluid solubility values (12.6 μM to 13.8 mM), Caco-2 permeability coefficients (1.2 × 10(-6)cm/s to 90.7 × 10(-6)cm/s) and in vitro-predicted human in vivo intrinsic clearance values (0 to 159 ml/min/kg).