1,2,3-Triazole-containing derivatives of rupestonic acid: click-chemical synthesis and antiviral activities against influenza viruses.

Two series of rupestonic acid derivatives, (1-substituted-1H-1,2,3-triazol-4-yl)methyl 2-((5R,8S,8aS)-3,8-dimethyl-2-oxo-1,2,4,5,6,7,8,8a-octahydroazulen-5-yl)acrylate and N-(1-substituted-1H-1,2,3-triazol-4-yl)methyl 2-((5R,8S,8aS)-3,8-dimethyl-2-oxo-1,2,4,5,6,7,8,8a-octahydroazulen-5-yl)acrylamide were easily and efficiently synthesized via click chemistry. These compounds were tested for their in vitro activities against various strains of influenza A virus (H1N1, oseltamivir resistant H1N1, H3N2) and influenza B virus. The results showed that nine compounds were active against the H1N1 strain of influenza A virus and among them the best one 14a, was as active as the reference drugs, Oseltamivir and Ribavirin.

Synthesis and bioactivity of 5-(1-aryl-1H-tetrazol-5-ylsulfanylmethyl)-N-xylopyranosyl-1,3,4-oxa(thia)diazol-2-amines.

A series of new N'-[N-(2,3,4-tri-O-acetyl-β-d-xylopyranosyl)thiocarbamoyl]-2-[(1-aryl-1H-tetrazol-5-yl)sulfanyl]acetohydrazides 5a-5e were synthesized rapidly in high yields from 2-(1-aryl-1H-tetrazol-5-ylsulfanyl)acetohydrazides 3a-3e and 2,3,4-tri-O-acetyl-β-d-xylopyranosyl isothiocyanate 4, then 5a-5e were converted to a series of new 5-(1-aryl-1H-tetrazol-5-ylsulfanylmethyl)-N-(2,3,4-tri-O-acetyl-β-D-xylopyranosyl)-1,3,4-oxadiazole-2-amines 6a-6e and 5-(1-aryl-1H-tetrazol-5-ylsulfanylmethyl)-N-(2,3,4-tri-O-acetyl-β-D-xylopyranosyl)-1,3,4-thiadiazole-2-amines 7a-7e, respectively under mercuric acetate/alcohol system or acetic anhydride/phosphoric acid system, then deacetylated in the solution of CH(3)ONa/CH(3)OH. All of the novel compounds were characterized by IR, (1)H NMR, (13)C NMR, MS and elemental analysis. The structures of compounds 2e, 3e, 5a and 5c have been determined by X-ray diffraction analysis.

Greenhouse gas emissions from a constructed wetland for municipal sewage treatment.

The fluxes of greenhouse gases (methane and nitrous oxide) emission from a constructed wetland in the Eastern China as municipal sewage treatment were measured from June 1999 to August 2000 by the closed chamber method. The constructed wetland for municipal sewage treatment is a significant source of methane, up to 976.6 x 10(6) g CH4/a, which was emitted from the constructed wetland with the area of 495,000 m2 and wastewater loading rate of 12,000 m3/d.