Two new 5-alkylpyrrole-2-carboxaldehyde derivatives,mycalenitrile-15（1） and mycalenitrile-16（2）,along with five known related ones（3-7）,were isolated from the South China Sea sponge Mycale lissochela.The structures of the new compounds were elucidated on the basis of extensive spectroscopic analysis and by comparison of their NMR data with those reported in the literature.In bioassay,compounds 1 and 7 exhibited significant PTPIB（Protein-tyrosine phosphatase 1B,a recognized target for diabetes and obesity） inhibitory activities with IC（50） values of 8.6 and 3.1 μmoI/L,respectively.A preliminary SAR analysis of the isolated compounds with their PTP1 B inhibitory effects was described.
Objective To isolate and identify the chemical constituents from mycelia and spores of the fungus Cordyceps cicadae,respectively.Methods The chemical constituents were isolated and purified by repeated silica gel,Sephadex LH-20,and reversed phase HPLC.The structures of these compounds were elucidated on the basis of extensive spectroscopic analysis,including 1 D and 2D NMR.Results Nine known sterols such as ergosterol（1）,ergosterol peroxide（2）,9,11-dehydroergosterol peroxide（3）,3β,5α,9α-trihydroxy-（22E,24R）-ergosta-7,22-dien-6-one（4）,3β,5α,9α,14α-tetrahydroxy-（22E,24R）-ergosta-7,22-dien-6-one（5）,5 α,6α-e poxy-（22 E,,24 R）-e rgosta-8（14）,22-diene-3α,7α-diol （6）, 3β,5α,6β-（22E,24R）-ergosta-7,22-dien-3,5,6-triol （7）, 3β,5α,6α-6- methoxyergosta-（22E,24R）-7,22-diene-3,5-diol （8）, 4-hydroxy-17R-methylincisterol （9）, together with a resorcinol derivative, 5-n-nonadecylresorcinol （10）, a cydo- desipeptide, beauvericin （11）, and a nucleoside, N^6-（2-hydroxyethyl）adenosine （12） were successively isolated from the cultivated C. cicadaemycelia and spores. Conclusion Compounds 3-10 are reported for the first time from the title sample, beauvericin exhibits significant cytotoxicity against human leukemia cell line and human lung cancer cell line.
The efficient synthesis of （S）-dihydroresorcylide （la） along with trans-resorcylide dimethyl ether （2b）, was achieved in linear 9 steps from commercially available orcinol monohydrate （6） with esterification, carbonylation, and ring-closing metathesis （RCM） as the key steps in the synthetic sequence.
Three new highly oxidative cembranoids,sarcophytrols D-F(1-3),were obtained from the South China Sea soft coral Sarcophyton trocheliophorum,along with two known related ones(4 and 5).Their structures were elucidated by extensive spectroscopic analyses and by comparison with literature data.The discovery of these new secondary metabolites enriched the family of cembranoids deduced from the title animal.
A new trijugin-type limonoid,cipatrijugin G(1),together with the related known cipatrijugin A(2),were isolated from the aerial parts of Cipadessa cinerascens.The structure of the new compound was determined by extensive analysis of its spectroscopic data and by comparison of its NMR data with those reported in the literature.Compound 1 showed cytotoxicity against tumor cell line A549 with an IC_(50) value of 9.78μM.This is the first report of a trijugin-type limonoid bearing aγ-hydroxybutenolide unit,in comparison to the common furan unit as ring E.
A bicyclic depsipeptide, chromopeptide A(1), was isolated from a deep-sea-derived bacterium Chromobacterium sp. HS-13-94. Its structure was determined by extensive spectroscopic analysis and by comparison with a related known compound. The absolute configuration of chromopeptide A was established by X-ray diffraction analysis employing graphite monochromated Mo K_α radiation(λ ? 0.71073 ?) with small Flack parameter 0.03. Chromopeptide A suppressed the proliferation of HL-60, K-562, and Ramos cells with average IC_(50) values of 7.7, 7.0, and 16.5 nmol/L, respectively.
