In vitro biological activities including anti-phytopathogenic fungi, antibacterial, antifeedant and herbicidal activities of the extracts from the heartwoods of Mansonia gagei Drumm. were evaluated. The dichlorometha...In vitro biological activities including anti-phytopathogenic fungi, antibacterial, antifeedant and herbicidal activities of the extracts from the heartwoods of Mansonia gagei Drumm. were evaluated. The dichloromethane （DCM） extract displayed antifungal activity against four plant pathogenic fungi （Altemaria porri, Colletotrichum gloeosporioides, Fusarium oxysporum and Phytophthora parasitica） higher than the methanolic （MeOH） extract. The separation of the DCM extract using bioassay guided antifungal activity against P. parasiUca led to the isolation of mansorins A, B, and C, mansonones C, E, G and H. Among isolated compounds, mansonone E displayed the highest antifungal activity against P. parasitica, followed by mansonone C, mansorin B and mansonone G. This potent compound revealed the same minimum inhibitory concentrations （MIC） of 31 μg mL-1 against C. gloeosporioides and P. parasitica, and minimum fungicidal concentration （MFC） of 31 and 125 μg mL-1, respectively. Moreover, mansonone E exhibited highly significant antibacterial activity against both Xanthomonas oryzae pv. oryzae （Xoo） and X. oryzae pv. oryzicola （Xoc） with MIC and minimum bactericidal concentration （MBC） as 7.8 and 〉500μg mL-1, respectively. This compound furthermore could inhibit the feed of Spodoptera litura with 45.9% antifeedant and significantly herbicidal activity reduced the shoot and root growth of Brassica chinensis, Oryza sativa, Mimosa pigra and Echinochlooa crus-galli. Mansonone E has potential as a new natural pesticide for agricultural plant pathogen management.展开更多
An asymmetric total synthesis of mansonone P and R were achieved, in whichintroduction of hydroxy substituent at position 2 was performed by Sharpless dihydroxylation ofsily enol ether.
1-[1-（Benzyloxy）-3-methylnaphthalen-4-yloxy]propan-2-one （la） took place a cyclization, debenzylation and oxidation to form 9-substitued benzo[de]chromene-7,8-dione （2a） and 5-benzyl-9-substitued benzo[de]chrome...1-[1-（Benzyloxy）-3-methylnaphthalen-4-yloxy]propan-2-one （la） took place a cyclization, debenzylation and oxidation to form 9-substitued benzo[de]chromene-7,8-dione （2a） and 5-benzyl-9-substitued benzo[de]chromene-7,8-dione （3a）. The mechanisms for these reactions were discussed.展开更多
基金the office of the Higher Education Commission,Thailand for supporting grant fund under the program Strategic Scholarships for Frontier Research Network for the Ph D Program Thai Doctoral degree for this research (77/2551)the 90th Anniversary of Chulalongkorn University Fund (Ratchadaphiseksomphot Endowment Fund,GCUGR11244525026D24)
文摘In vitro biological activities including anti-phytopathogenic fungi, antibacterial, antifeedant and herbicidal activities of the extracts from the heartwoods of Mansonia gagei Drumm. were evaluated. The dichloromethane （DCM） extract displayed antifungal activity against four plant pathogenic fungi （Altemaria porri, Colletotrichum gloeosporioides, Fusarium oxysporum and Phytophthora parasitica） higher than the methanolic （MeOH） extract. The separation of the DCM extract using bioassay guided antifungal activity against P. parasiUca led to the isolation of mansorins A, B, and C, mansonones C, E, G and H. Among isolated compounds, mansonone E displayed the highest antifungal activity against P. parasitica, followed by mansonone C, mansorin B and mansonone G. This potent compound revealed the same minimum inhibitory concentrations （MIC） of 31 μg mL-1 against C. gloeosporioides and P. parasitica, and minimum fungicidal concentration （MFC） of 31 and 125 μg mL-1, respectively. Moreover, mansonone E exhibited highly significant antibacterial activity against both Xanthomonas oryzae pv. oryzae （Xoo） and X. oryzae pv. oryzicola （Xoc） with MIC and minimum bactericidal concentration （MBC） as 7.8 and 〉500μg mL-1, respectively. This compound furthermore could inhibit the feed of Spodoptera litura with 45.9% antifeedant and significantly herbicidal activity reduced the shoot and root growth of Brassica chinensis, Oryza sativa, Mimosa pigra and Echinochlooa crus-galli. Mansonone E has potential as a new natural pesticide for agricultural plant pathogen management.
基金This work was supported by NNSFC(QT program)NNSFC(20372026)+1 种基金SRF for ROCS.SEM,Gansu Science Foundation(No,YS031-A21-001)Lanzhou University Foundation(No.5715220101).
文摘An asymmetric total synthesis of mansonone P and R were achieved, in whichintroduction of hydroxy substituent at position 2 was performed by Sharpless dihydroxylation ofsily enol ether.
基金We are indebted to the National Natural Science Foundation of China （No.20272085,20472117）the Guangzhou City Science Foundation,the Guangdong Provincial Science Foundation（031594）the Scientific Research Foundation for the Returned 0verseas Chinese Scholars,and the HongKong Polytechnic University Area of Strategic Development Fund for financial support of this study.
文摘1-[1-（Benzyloxy）-3-methylnaphthalen-4-yloxy]propan-2-one （la） took place a cyclization, debenzylation and oxidation to form 9-substitued benzo[de]chromene-7,8-dione （2a） and 5-benzyl-9-substitued benzo[de]chromene-7,8-dione （3a）. The mechanisms for these reactions were discussed.
