Streamlined Chemo-Enzymatic Synthesis of Molnupiravir via Lipase Catalyst.

An enzymatic approach for the synthesis of Molnupiravir has been developed using immobilized lipase as a biocatalyst. This method involves a concise process of the regioselective esterification of uridine with isobutyric anhydride using Lipase (Addzyme-011). This efficient route gets 97% conversion of uridine 3, with an overall 73% yield of molnupiravir 1 in two steps. The use of inexpensive and easily available lipase makes the synthesis cost-effective and accessible globally, promoting the principles of green chemistry.

Lipase mediated new chemo-enzymatic synthesis of (RS)-, (R)-, and (S)-bunolol.

The ß-adrenergic receptor blocking agents are an important class of drug molecules. The present study reports a new chemo and chemo-enzymatic synthetic process for (RS)-, (R)-, and (S)-bunolol, one of the potent ß-adrenergic receptor blocker. In chemo-enzymatic process, CAL L4777 lipase was employed for enantioselective kinetic resolution to synthesize the enantiopure (R)-alcohol and (S)-ester from the corresponding racemic alcohol. Thereafter, the corresponding (R)-alcohol and deacylated (S)-ester were treated with tert-butylamine to produce (S)- and (R)-bunolol, respectively. In chemical approach, epichlorohydrin (RS-, R-, and S-) was used as a starting material via respective (RS)-, (S)-, and (R)-glycidyl ether as intermediates for synthesis of enantiomeric (RS)-, (R)-, and (S)-bunolol. In comparison between two approaches, it was found that the chemo-enzymatic process was more effective and resulted in enantiomeric excess of 98% with 35% yield.