Four polycyclic ten-membered lactones possessing unprecedented 10/6/5 tricyclic ring skeleton,named eutypetides A—D(1—4),and an intriguing polyketide containing a hexahydroisobenzofuran-1(3H)-one motif,named eutypet...Four polycyclic ten-membered lactones possessing unprecedented 10/6/5 tricyclic ring skeleton,named eutypetides A—D(1—4),and an intriguing polyketide containing a hexahydroisobenzofuran-1(3H)-one motif,named eutypetide E(5)were isolated from the marine-derived fungus Eutypella sp.F0219,together with three new related biosynthetic polyketides eutypetides F—H(6—8).The absolute configurations of 1—5 were unequivocally determined by single-crystal X-ray diffraction analyses(Cu Kα),modified Mosher's method and electronic circular dichroism(ECD)calculations.Eutypetides G(7)showed remarkable anti-inflammatory activity and could reduce the mRNA expression of proinflammatory cytokines IL-1β,IL-6,TNF-α,and iNOS induced by LPS.Most notably,compounds 1—4 were formed biogenetically from 6—7 via the key intramolecular[4+2]cycloaddition,while compound 5 could be constructed biogenetically from 8 through the intramolecular[4+2]cycloaddition.All the above eight polyketides are proposed to originate from a C10 and a C6 fatty acid.展开更多
基金supported by the National Natural Science Foundation of China(82204275,82160653,and 22267006)Natural Science Foundation of Hainan Province(323Ms014 and 222QN303)Fundamental Research Funds for Hainan University(KYQD(ZR)-22088 and KYQD(ZR)-21089)。
文摘Four polycyclic ten-membered lactones possessing unprecedented 10/6/5 tricyclic ring skeleton,named eutypetides A—D(1—4),and an intriguing polyketide containing a hexahydroisobenzofuran-1(3H)-one motif,named eutypetide E(5)were isolated from the marine-derived fungus Eutypella sp.F0219,together with three new related biosynthetic polyketides eutypetides F—H(6—8).The absolute configurations of 1—5 were unequivocally determined by single-crystal X-ray diffraction analyses(Cu Kα),modified Mosher's method and electronic circular dichroism(ECD)calculations.Eutypetides G(7)showed remarkable anti-inflammatory activity and could reduce the mRNA expression of proinflammatory cytokines IL-1β,IL-6,TNF-α,and iNOS induced by LPS.Most notably,compounds 1—4 were formed biogenetically from 6—7 via the key intramolecular[4+2]cycloaddition,while compound 5 could be constructed biogenetically from 8 through the intramolecular[4+2]cycloaddition.All the above eight polyketides are proposed to originate from a C10 and a C6 fatty acid.
