Abstract:
Thiasporine A was a natural product containing phenylthiazole ring isolated from the marine-derived
Actinomycetospora chlora SNC-032 and showed cytotoxicity against the lung cancer cell line H2122. Thiasporine A (
4o ) and 29 Thiasporine A analogues (
3a -
3o ,
4a -
4n ) were synthesized using substituted benzonitriles as starting material, among which 24 analogues have not been reported in literature. Their structures were characterized by
1H NMR,
13C NMR and HRMS spectra. The fungicidal activities of Thiasporine A and its analogues were tested. The results indicated that most of Thiasporine A analogues exhibited certain fungicidal activities. Compounds
3e and
3i were found to have the inhibition rates of 84.5% and 84.4% against
Rhizoctonia solani at a concentration of 200 μmol/L, with the EC
50 values of 17.3 μmol/L and 21.9 μmol/L, respectively. Compounds
4b and
4j displayed the inhibition rate of 100% against
Selerotium rolfsii at 200 μmol/L. compound
4b demonstrated an inhibition rate of 83.3% against
Phytophthora parasitica at 200 μmol/L, which was better than the commercial thifluzamide. The inhibition rates of compound
3g against five fungi were all higher than 70% at 200 μmol/L.