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Phytochemical investigation of the methanol extract of the aerial parts of Polygonum glabrum afforded one new natural product (-)-2-methoxy-2-butenolide-3-cinnamate (1) along with six known compounds, β-hydroxyfriedalanol (2), 3-hydroxy-5-methoxystilbene (3), (-) pinocembrin (4), sitosterol-(6'-O-palmitoyl)-3-O-β-D-glucopyranoside (5), (-) pinocembrin-5-methyl ether (6) and sitosterol-3-O-β-D-glucopyranoside (7). Compound 1 showed promising in vitro anti-HIV-1 activity against primary isolates HIV-1(UG070) (X4, subtype D) and HIV-1(VB59) (R5, subtype C) assayed using TZM-bl cell line with IC50 in the range of 15.68-22.43 μg/mL. The extract showed TI in the range of 19.19-27.37 with IC50 in the range of 10.90-15.55 μg/mL. Compounds 1, 3 and 4 exhibited in vitro anti-mycobacterium activity against Mycobacterium tuberculosis H37Ra with IC50 values of 1.43, 3.33 and 1.11 μg/mL in dormant phase and 2.27, 3.33 and 1.21 μg/mL in active phase, respectively. Compound 4 was found to be the most active antiproliferative with IC50 values of 1.88-11.00 μg/mL against THP-1, A549, Panc-1, HeLa and MCF7 cell lines.

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Natural polysaccharides supported tetrabutylammonium fluoride (TBAF) complexes are prepared and found to be highly stable and selective fluoride source for well‐renowned nucleophilic (SN2 type) fluorination reactions for the first time. Bacterial cellulose, plant cellulose, pectin, and starch derived TBAF complexes are synthesized, characterized (using SEM, TEM, and NMR techniques) and studied for their stability and reactivity. Heterogeneous bacterial cellulose‐TBAF complex (NBu4(Bac‐cell‐OH)F) 1 was found to be highly stable and non‐hygroscopic among all complexes, which gave high yields of fluorinated products in multi‐gram scale in shorter reaction time. The primarily developed batch protocol was extended to solid‐solid continuous flow reaction using an in‐house built screw reactor, which furnished products in a few seconds of residence time (tR=20–25 sec) and excellent yields.

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Fluoroarene-mediated trifluoromethylation of carboxylic acids for the synthesis of trifluoromethyl ketones is disclosed. The fluoroarene activates the acid group and generates the fluoride source in situ for the trifluoromethylation reaction. The present protocol is safe and metal-free, operates under mild reaction conditions, and does not require any external additives to generate trifluoromethyl anion. The current transformation provides good functional group tolerance and also delivers 92% and 88% yields of trifluoromethyl ketones in batch and continuous flow, respectively.