Several alkynes and azides were prepared starting from betulinic acid and Baylis-Hillman reaction-derived allylic alcohols. These alkynes and azides were then coupled under click cycloaddition conditions to obtain functionalized betulinic acid-triazole conjugates. Similarly, pyrazinyl- and indolylbetulinic acid-triazoles were also prepared employing cycloaddition chemistry. All the synthetic compounds were tested for their cytotoxicity against murine breast cancer (4T1) and human pancreatic cancer (MIA PaCa-2) cell lines. Based on these in vitro assays, two series of compounds have been identified as lead compounds for further development.Download high-res image (151KB)Download full-size image

Several derivatives of aminobenzoboroxole have been prepared starting from 2-boronobenzaldehyde. All of these derivatives have been evaluated for their anti-mycobacterial activity on Mycobacterium smegmatis and cytotoxicity on breast cancer cell line MCF7. Based on these studies, all the tested molecules have been found to be generally non-toxic and benzoboroxoles with unsubstituted (primary) amines have been found to exhibit good anti-mycobacterial activity. Some of the key compounds have been evaluated for their anti-tubercular activity on Mycobacterium tuberculosis H37Rv using 7H9 and GAST media. 7-Bromo-6-aminobenzoboroxole 4 has been identified as the lead candidate compound for further development.

2-Formylphenylboronic acids upon reaction with activated olefins such as acrylates, methyl vinyl ketone, and acrylonitrile provide functionalized benzoboroxoles. The corresponding homologated benzoboroxoles were synthesized via the reaction of 2-formylphenylboronic acids with α-bromomethylacrylates.2-Formylphenylboronic acids upon reaction with activated olefins such as acrylates, methyl vinyl ketone, and acrylonitrile provide functionalized benzoboroxoles. The corresponding homologated benzoboroxoles were synthesized via the reaction of 2-formylphenylboronic acids with α-bromomethylacrylates.