A series of amide derivatives of 1,2-isoxazole combined with 1,2,4-thiadiazole are synthesized 11a–11j. Their chemical structures are confirmed by 1H and 13C NMR, and mass spectra. The products are...

The present work describes the synthesis of molnupiravir by employing commercially available inexpensive materials in two steps with an overall yield of 85.7%. The synthetic methodology starts with an eco-friendly starting material, that is, cytidine and establishes an alternative way to avoid costly enzyme mediated reactions. This synthetic strategy involves a selective acylation of cytidine as the first key step followed by the second step, that is, hydroxamination reaction. The major advantage of this protocol is that it is completely free of protection and deprotection reactions. Chemoselective acylation of cytidine's primary alcohol was achieved using isobutyryl chloride, Et₃N, and DMF solvent (89.3% yield). The aqueous phase transformation was achieved for the hydroxamination reaction with a 96% yield.

Clobetasol Propionate is a highly strong corticosteroid that is used in a variety of topical medication formulations, including foam, ointment, lotion, spray and shampoo; with a dosage strength of 0.05% (w/w). The goal of this research was to identify and characterize a substantial unknown impurity (UK) detected during the stability testing of a Clobetasol Propionate foam pharmaceutical product in accelerated conditions (40°C and 75% relative humidity). Developing a single, robust and accurate HPLC method that is LC–MS compatible for quantifying all 14 potential Clobetasol Propionate impurities in therapeutic drugs is another goal. Preparative column chromatography was used to separate the impurity, and spectroscopic techniques like IR, NMR and MS were used to characterize its structure. The structure of isolated UK was effectively characterized and defined using spectroscopic data evaluation. The chromatographic method has also been validated according to the International Conference on Hominization's Q (2) quality guidelines. The isolated and characterized impurity had the same equivalence as the impurity found during stability testing. Precision, accuracy, linearity, robustness and ruggedness are all met in the method validation data.