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
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
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
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
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).
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.
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.
