Eight cembrane-type diterpenoids, namely,(t)-(6 R)-6-hydroxyisosarcophytoxide(1),(t)-(6 R)-6-acetoxyisosarcophytoxide(2),(t)-17-hydroxyisosarcophytoxide(3), sarcomililatins A–D(4–7), and sarcomililatol(8), were isol...Eight cembrane-type diterpenoids, namely,(t)-(6 R)-6-hydroxyisosarcophytoxide(1),(t)-(6 R)-6-acetoxyisosarcophytoxide(2),(t)-17-hydroxyisosarcophytoxide(3), sarcomililatins A–D(4–7), and sarcomililatol(8), were isolated from the soft coral Sarcophyton mililatensis collected from Weizhou Island, Guangxi Autonomous Region, together with 2 known related analogues,(t)-isosarcophytoxide(9) and(t)-isosarcophine(10). The structures of these compounds were elucidated by a combination of detailed spectroscopic analyses, chemical methods, and comparison with reported data.The absolute configuration of compound 1 was established by the modified Mosher's method, while the absolute configurations of compounds 4 and 5 were assigned by electronic circular dichroism(ECD)spectroscopy and that of compound 8 was established by time-dependent density functional theory electronic circular dichroism(TD-DFT ECD) calculation. In in vitro bioassays, compound 9 displayed significant cytotoxicity against the human cancer cell lines human promyelocytic leukemia cells(HL-60)and human lung adenocarcinoma cells(A-549) with IC_(50) values of 0.7870.21 and 1.2670.80 μmol/L,respectively. Compounds 4 and 9 also showed moderate inhibitory effects on the TNFα-induced Nuclear factor kappa B(NF-κB, a therapeutical target in cancer) activation, showing IC_(50) values of 35.23712.42 and 22.5274.44 μmol/L, respectively.展开更多
From the 1-BuOH-soluble fraction of a MeOH extract of the leaves of Symplocos cochinchinensis var. philippinensis, 12 compounds were isolated. Spectroscopic analyses of compounds 1 - 3 established their structures to ...From the 1-BuOH-soluble fraction of a MeOH extract of the leaves of Symplocos cochinchinensis var. philippinensis, 12 compounds were isolated. Spectroscopic analyses of compounds 1 - 3 established their structures to be megastig-mane glycosides, named symplocosionosides A-C. The absolute structure of 1 was determined by the modified Mosher’s method. Compound 4 was found to be a neolignan glucoside and named symplocosneolignan. The structures of com-pounds 5 and 6, named symplocosins A and B, were elucidated to be the saponins of hederagenin sugar esters. The structures of the remaining known compounds (7 - 12) were identified by comparison of spectroscopic data with those reported in the literature.展开更多
A new sesquiterpene lactone(1)and a new aromatic glycoside(2),together with three known compounds(3–5)were isolated from the stem bark of Illicium difengpi K.I.B et K.I.M.Their structures were determined by spectrosc...A new sesquiterpene lactone(1)and a new aromatic glycoside(2),together with three known compounds(3–5)were isolated from the stem bark of Illicium difengpi K.I.B et K.I.M.Their structures were determined by spectroscopic methods,including 1D and 2D NMR,HRESIMS,and chemical methods.The absolute configuration of the secondary alcohol in 1 was confirmed by Mosher’s method.Compound 2 exhibited significant anti-inflammatory activity with IC50 value of 6.72 mmol/L.展开更多
Two new polyoxygenated steroids, reticulatic acid （1） and reticulatin （2）, together with a known compound 3,22,25-trihydroxy-16-24,20-24-bisepoxy-3β,16β,20S,22R,24S-cholest-5-ene （3）, were isolated from the CH...Two new polyoxygenated steroids, reticulatic acid （1） and reticulatin （2）, together with a known compound 3,22,25-trihydroxy-16-24,20-24-bisepoxy-3β,16β,20S,22R,24S-cholest-5-ene （3）, were isolated from the CH2Cl2/ EtOH extract of the South China Sea gorgonian coral Subergorgia reticulata. Their structures were established on the basis of extensive spectroscopic analysis. The absolute stereochemistry of compounds 2 and 3 was determined by the X-ray crystallographic analysis and the Mosher ester determination.展开更多
Fungal symbionts co-evolve with hosts and microbial co-inhabitants to acquire an unpredictable potential for producing novel bioactive metabolites,but the knowledge about the topic remains patchy and superficial.Here ...Fungal symbionts co-evolve with hosts and microbial co-inhabitants to acquire an unpredictable potential for producing novel bioactive metabolites,but the knowledge about the topic remains patchy and superficial.Here we present the chemical characterization of acatulides A-G(1-7)as architecturally unprecedented macrolides from the solid-state culture of Acaulium album H-JQSF,an arthropod-associated fungus.The acatulide structures were elucidated by spectroscopic analysis,modified Mosher's method and single-crystal X-ray diffraction.The plausible biosynthetic pathways for compounds 1-4 are proposed.Interestingly,acatulides B-D(2-4)and G(7)were demonstrated to be neuroprotective against the 1-methyl-4-phenylpyridinium(MPP+)-induced damage to SH-SY5Y cells and nematode Caenorhabditis elegans(C.elegans).展开更多
Polyhydroxy enyne compound （＋）-（1＇S, 2R, 3S, 5S, 6S）-5,6-dimethoxy-5, 6-dimethyl- 2-（1＇-hydroxylpropyl-2-ne）-3-vinyl-l,4-dioxane has been synthesized from D-（-）-tartaric acid. A new chiral center was establ...Polyhydroxy enyne compound （＋）-（1＇S, 2R, 3S, 5S, 6S）-5,6-dimethoxy-5, 6-dimethyl- 2-（1＇-hydroxylpropyl-2-ne）-3-vinyl-l,4-dioxane has been synthesized from D-（-）-tartaric acid. A new chiral center was established by nucleophilic addition with 87% de. The modified Mosher＇s method was employed to confirm the absolute configuration of 17, which assigned the S-configuration at the new chiral center.展开更多
Verrucosidins,a methylatedα-pyrone class of polyketides rarely reported upon,have been implicated in one or more neurological diseases.Despite the signifcance of verrucosidins as neurotoxins,the absolute confguration...Verrucosidins,a methylatedα-pyrone class of polyketides rarely reported upon,have been implicated in one or more neurological diseases.Despite the signifcance of verrucosidins as neurotoxins,the absolute confgurations of most of the derivatives have not been accurately characterized yet.In this study,three pairs of C-9 epimeric verrucosidin derivatives,including the known compounds penicyrones A and B(1a/1b)and 9-O-methylpenicyrones A and B(2a/2b),the new compounds 9-O-ethylpenicyrones A and B(3a/3b),together with the related known derivative verrucosidin(4),were isolated and identifed from the culture extract of Penicillium cyclopium SD-413,which was obtained from the marine sediment collected from the East China sea.Their structures were established based on an in-depth analysis of nuclear magnetic resonances(NMR)and mass spectroscopic data.Determination of the absolute confgurations of these compounds was accomplished by Mosher’s method and time-dependent density functional theory(TDDFT)calculations of electronic circular dichroism(ECD)and optical rotation(OR).The confgurational assignment of penicyrone A demonstrated that the previously reported C-6 absolute confguration of verrucosidin derivatives needs to be revised from(6S)to(6R).The 9R/9S epimers of compounds 1–3 were found to exhibit growth inhibition against some pathogenic bacteria,indicating that they have potential as lead compounds for the creation of antimicrobial agents.展开更多
α-Hydroxy ketones are frequently involved in biologically important compounds and,therefore,the determination of the stereochemistry of these structural elements has attracted the attention in natural products chemis...α-Hydroxy ketones are frequently involved in biologically important compounds and,therefore,the determination of the stereochemistry of these structural elements has attracted the attention in natural products chemistry.In this paper a simpler Mosher′s method was developed from the modified Mosher′s method.It only need one configuration of MTPA to determine the absolute configurations of four α-hydroxy ketones with their（S）-and（R）-MTPA esters using（）1H NMR.The signals of protons on the same side with phenyl ring will be in the higher field than those of on the different side ones.Consequently according to the model the main configuration of compounds 1,2,3 and 4 were determined as S,R,R and S, respectively.展开更多
基金supported by the Natural Science Foundation of China(Nos.41506187,81520108028,21672230 and 81603022)NSFC-Shandong Joint Fund for Marine Science Research Centers(No.U1606403)+1 种基金SCTSM Project(No.15431901000)the SKLDR/SIMM Projects(SIMM 1705ZZ-01)
文摘Eight cembrane-type diterpenoids, namely,(t)-(6 R)-6-hydroxyisosarcophytoxide(1),(t)-(6 R)-6-acetoxyisosarcophytoxide(2),(t)-17-hydroxyisosarcophytoxide(3), sarcomililatins A–D(4–7), and sarcomililatol(8), were isolated from the soft coral Sarcophyton mililatensis collected from Weizhou Island, Guangxi Autonomous Region, together with 2 known related analogues,(t)-isosarcophytoxide(9) and(t)-isosarcophine(10). The structures of these compounds were elucidated by a combination of detailed spectroscopic analyses, chemical methods, and comparison with reported data.The absolute configuration of compound 1 was established by the modified Mosher's method, while the absolute configurations of compounds 4 and 5 were assigned by electronic circular dichroism(ECD)spectroscopy and that of compound 8 was established by time-dependent density functional theory electronic circular dichroism(TD-DFT ECD) calculation. In in vitro bioassays, compound 9 displayed significant cytotoxicity against the human cancer cell lines human promyelocytic leukemia cells(HL-60)and human lung adenocarcinoma cells(A-549) with IC_(50) values of 0.7870.21 and 1.2670.80 μmol/L,respectively. Compounds 4 and 9 also showed moderate inhibitory effects on the TNFα-induced Nuclear factor kappa B(NF-κB, a therapeutical target in cancer) activation, showing IC_(50) values of 35.23712.42 and 22.5274.44 μmol/L, respectively.
文摘From the 1-BuOH-soluble fraction of a MeOH extract of the leaves of Symplocos cochinchinensis var. philippinensis, 12 compounds were isolated. Spectroscopic analyses of compounds 1 - 3 established their structures to be megastig-mane glycosides, named symplocosionosides A-C. The absolute structure of 1 was determined by the modified Mosher’s method. Compound 4 was found to be a neolignan glucoside and named symplocosneolignan. The structures of com-pounds 5 and 6, named symplocosins A and B, were elucidated to be the saponins of hederagenin sugar esters. The structures of the remaining known compounds (7 - 12) were identified by comparison of spectroscopic data with those reported in the literature.
基金supported by the National Science and Technology Project of China(No.2009ZX09311-004)the Natural Science Foundation of China(No.21072234).
文摘A new sesquiterpene lactone(1)and a new aromatic glycoside(2),together with three known compounds(3–5)were isolated from the stem bark of Illicium difengpi K.I.B et K.I.M.Their structures were determined by spectroscopic methods,including 1D and 2D NMR,HRESIMS,and chemical methods.The absolute configuration of the secondary alcohol in 1 was confirmed by Mosher’s method.Compound 2 exhibited significant anti-inflammatory activity with IC50 value of 6.72 mmol/L.
基金Project supported by the Knowledge Innovation Program of Chinese Academy of Sciences （No. KZCX3-SW-216）, Natural Science Foundation （No. 2003-11） of Guangdong Province and Research Program of Croucher Foundation.
文摘Two new polyoxygenated steroids, reticulatic acid （1） and reticulatin （2）, together with a known compound 3,22,25-trihydroxy-16-24,20-24-bisepoxy-3β,16β,20S,22R,24S-cholest-5-ene （3）, were isolated from the CH2Cl2/ EtOH extract of the South China Sea gorgonian coral Subergorgia reticulata. Their structures were established on the basis of extensive spectroscopic analysis. The absolute stereochemistry of compounds 2 and 3 was determined by the X-ray crystallographic analysis and the Mosher ester determination.
基金co-financed by the grants from National Nature Science Foundation of China(Nos.81991523 and 81991524)National Science and Technology Innovation 2030-Major Program of“Brain Science and Brain-Like Research”(No.2022ZD0211804)。
文摘Fungal symbionts co-evolve with hosts and microbial co-inhabitants to acquire an unpredictable potential for producing novel bioactive metabolites,but the knowledge about the topic remains patchy and superficial.Here we present the chemical characterization of acatulides A-G(1-7)as architecturally unprecedented macrolides from the solid-state culture of Acaulium album H-JQSF,an arthropod-associated fungus.The acatulide structures were elucidated by spectroscopic analysis,modified Mosher's method and single-crystal X-ray diffraction.The plausible biosynthetic pathways for compounds 1-4 are proposed.Interestingly,acatulides B-D(2-4)and G(7)were demonstrated to be neuroprotective against the 1-methyl-4-phenylpyridinium(MPP+)-induced damage to SH-SY5Y cells and nematode Caenorhabditis elegans(C.elegans).
文摘Polyhydroxy enyne compound （＋）-（1＇S, 2R, 3S, 5S, 6S）-5,6-dimethoxy-5, 6-dimethyl- 2-（1＇-hydroxylpropyl-2-ne）-3-vinyl-l,4-dioxane has been synthesized from D-（-）-tartaric acid. A new chiral center was established by nucleophilic addition with 87% de. The modified Mosher＇s method was employed to confirm the absolute configuration of 17, which assigned the S-configuration at the new chiral center.
基金Financial support by programs from the National Natural Science Foundation of China(U2006203)from the Senior User Project of RV KEXUE(KEXUE2020GZ02)is gratefully acknowledged.B.-G.W.appreciates the support of the RV KEXUE of the National Major Science and Technology Infrastructure from the Chinese Academy of Sciences(for sampling)The research work of the Hungarian authors was supported by the National Research,Development,and Innovation Ofce(K138672,FK134653).The Governmental Information-Technology Development Agency(KIFÜ)is acknowledged for CPU time。
文摘Verrucosidins,a methylatedα-pyrone class of polyketides rarely reported upon,have been implicated in one or more neurological diseases.Despite the signifcance of verrucosidins as neurotoxins,the absolute confgurations of most of the derivatives have not been accurately characterized yet.In this study,three pairs of C-9 epimeric verrucosidin derivatives,including the known compounds penicyrones A and B(1a/1b)and 9-O-methylpenicyrones A and B(2a/2b),the new compounds 9-O-ethylpenicyrones A and B(3a/3b),together with the related known derivative verrucosidin(4),were isolated and identifed from the culture extract of Penicillium cyclopium SD-413,which was obtained from the marine sediment collected from the East China sea.Their structures were established based on an in-depth analysis of nuclear magnetic resonances(NMR)and mass spectroscopic data.Determination of the absolute confgurations of these compounds was accomplished by Mosher’s method and time-dependent density functional theory(TDDFT)calculations of electronic circular dichroism(ECD)and optical rotation(OR).The confgurational assignment of penicyrone A demonstrated that the previously reported C-6 absolute confguration of verrucosidin derivatives needs to be revised from(6S)to(6R).The 9R/9S epimers of compounds 1–3 were found to exhibit growth inhibition against some pathogenic bacteria,indicating that they have potential as lead compounds for the creation of antimicrobial agents.
文摘α-Hydroxy ketones are frequently involved in biologically important compounds and,therefore,the determination of the stereochemistry of these structural elements has attracted the attention in natural products chemistry.In this paper a simpler Mosher′s method was developed from the modified Mosher′s method.It only need one configuration of MTPA to determine the absolute configurations of four α-hydroxy ketones with their（S）-and（R）-MTPA esters using（）1H NMR.The signals of protons on the same side with phenyl ring will be in the higher field than those of on the different side ones.Consequently according to the model the main configuration of compounds 1,2,3 and 4 were determined as S,R,R and S, respectively.
