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Many phytopathogenic fungi can easily infect crops, resulting in crop yield reductions. In continuation of our effort to develop natural product (NP)-based antifungal agents, a series of N -phenylpyrazole sarisan hybrids 6a - v were prepared via I 2 -mediated oxidative cyclization, and their structures were determined by various spectral analyses including IR, 1 H NMR and ESI-MS. Among all N- phenylpyrazole sarisan hybrids, compounds 6a , 6b , 6e , 6i , 6j and 6r showed more potent antifungal activity against at lest two phytopathogenic fungi than the commercial fungicide hymexazol. In particular, compound 6a exhibited more broad-spectrum and promising antifungal activity against three phytopathogenic fungi ( V. mali , F. oxysporum f.sp.niveum , and F. graminearum ) with the EC 50 values of 18.5, 37.4 and 12.6 μg/mL, respectively. Moreover, the structure-activity relationships (SARs) were also observed. Additionally, compounds 6a and 6e also exhibited relative low toxicity on normal LO2 cells. This work indicates that these N -phenylpyrazole sarisan hybrids would shed light on developing novel NP-based antifungal agents.

Many phytopathogenic fungi cause severe damage to crop yields. In continuation of our research aimed at the discovery and development of natural products-based fungicides, a series of thirty-one sarisan attached 3-phenylisoxazolines were synthesized and evaluated for their antifungal activities against five phytopathogenic fungi ( B. cinerea , C. lagenarium , A. solani, F. solani , and F. graminearum ). Among all title sarisan derivatives, compounds IV2 , IV14 and IV23 showed potent antifungal activity against some phytopathogenic fungi. In particular, compound IV2 exhibited a broad-spectrum and more potent antifungal activity against A. solani , F. solani, and F. graminearum than the commercial fungicide Hymexazol. In addition, compounds IV2 , IV14 and IV23 also displayed relative low toxicity on normal NRK-52E cells. This work will give some insights into the development of sarisan derivatives as new fungicide candidates in plant protection.

Natural products (NPs) are very important sources for the development of new drugs. Merrillianone and cycloparvifloralone, isolated from the roots, stems, and fruits of Illicium henryi Diels, are two natural sesquiterpene compounds. In continuation of our effort to discovery more effective neurotrophic compounds from NPs, a series of novel merrillianone/cycloparviforalone based esters 2a-i, 3a-g and 3i-q were prepared and their structures were characterized by 1H NMR, 13C NMR and IR spectral analyses. Furthermore, the spatial structure of compound 2h was unambiguously confirmed by X-ray crystallography. The neurite outgrowth-promoting activity results indicated that most of the target derivatives exhibited more potent neurite outgrowth-promoting activity than merrillianone and cycloparviforalone. Among all target derivatives, the neurite outgrowth-promoting activity of compounds 2a, 3a and 3b was about 2-fold stronger than that of their precursors merrillianone and cycloparviforalone, respectively. Besides, compounds 2a and 3a displayed relatively low cytotoxicity to normal GES-1 cells. Moreover, these derivatives had good hydrolytic stability. Finally, some interesting results of the structure-activity relationships (SARs) were also discussed. This work will pave the way for the development of merrillianone/cycloparviforalone derivatives as potential neurotrophic agents.

Glutathione is a tri-peptide consisting of L-glutamic acid, L-cysteine and glycine, widely applied to the pharmaceutical, food, and cosmetic industries. Also, GSH has potential application in the bioremediation of soil and water. A novel ATP regulating strategy based on the ATP-sensing riboswitch ydaO and polyphosphate kinase was developed. Besides, GshF from Streptococcus thermophile was introduced into the Escherichia coli BL 21. The GSH titer of the strain AYPGS(harboring pRSFDuet-ydaO-ppk-gshF) could reach 145.32 mg L−1 after 18 h fermentation, which was three times higher than that of the control and 37% higher than that of the strain AGP(harboring pRSFDuet-ppk-gshF). The results showed that S. thermophiles-derived GshF was insensitive to feedback inhibition caused by GSH and could greatly increase the GSH production. It also proved that the ATP regulating strategy could dynamically control the ATP level and enhance GSH production. Our proposed ATP regulating strategy will be potentially applicable for other ATP-driven metabolites.