Croton sublyratus (Euphorbiaceae) is a traditional medicinal plant used by the Thai populace to treat helminthic infections and dermatologic conditions. In present study, eight new labdane-type diterpenoids, crotonoids A-H (1-8) and one known analogue (9) were isolated from the aerial parts of C. sublyratus.
View Article and Find Full Text PDFThe genus L. is traditionally used in folk medicine to alleviate pain caused by various kinds of inflammation. In the present study, 10 undescribed salicin derivatives along with 5 known congeners were isolated from the barks of , and their structures were elucidated by spectroscopic analyses, single-crystal X-ray diffraction, electronic circular dichroism (ECD) calculations, and chemical conversions.
View Article and Find Full Text PDFNine previously unreported various types of monoterpenoid indole alkaloids, together with seven known analogues were isolated from the stem barks of Alstonia scholaris through a silica gel free methodology. The structures of 1-9 were elucidated by spectroscopic data analysis, electronic circular dichroism calculations, and single-crystal X-ray diffraction. Compound 1 is a modified echitamine-type alkaloid with a novel 6/5/5/7/6/6 hetero hexacyclic bridged ring system, and 8 and 9 exist as a zwitterion and trifluoroacetate salt, respectively.
View Article and Find Full Text PDFEleven densely functionalized new dihydro-β-agarofuran sesquiterpenoid derivatives, named maytenoids A-K (-), as well as one known analog, were isolated and characterized from . Their structures were assigned based on analysis of spectroscopic data and X-ray crystallography. Compounds - are macrocyclic sesquiterpene pyridine alkaloids generated by the respective acylation of the hydroxy groups at C-3 and C-13 of dihydro-β-agarofuran sesquiterpenoids via diverse pyridine dicarboxylic acids.
View Article and Find Full Text PDFChemical investigation of the twigs of (Phyllanthaceae) led to the isolation of 10 undescribed lignans, sumatranins A-J (-). Compounds - are unprecedented furopyran lignans characterized by a unique 2,3,3a,9a-tetrahydro-4-furo[2,3-]chromene heterotricyclic framework. Compounds and are rare 9'--dibenzylbutane lignans.
View Article and Find Full Text PDFNine undescribed diterpenoids, euphlactenoids A-I (1-9), including four ingol-type diterpenoids (1-4) with a 5/3/11/3-tetracyclic framework and five ent-pimarane-type diterpenoids (5-9), together with thirteen known diterpenoids (10-22), were identified from the leaves and stems of Euphorbia lactea Haw. The structures and absolute configurations of compounds 1-9 were unequivocally elucidated on the basis of spectroscopic analysis, ECD calculations and single crystal X-ray diffraction. Compounds 3 and 16 showed anti-HIV-1 effects with IC values of 1.
View Article and Find Full Text PDFLaeviganoids A-T (-), 20 new -clerodane-type diterpenoids featuring a 2-furanone (-) or a furan (-) ring, as well as six analogues (-), were isolated from the roots of . Their structures were determined by spectroscopic data analysis, experimental electronic circular dichroism measurements, and X-ray crystallographic studies. Compounds -, , -, and could influence the anti-inflammatory protumoral phenotype of macrophages.
View Article and Find Full Text PDFSeventeen new cephalotane-type diterpenoids, fortalides A-Q (1-17), along with five known analogues, were isolated from the seeds of var. . Their structures were determined by extensive spectroscopic methods, as well as electronic circular dichroism (ECD) and X-ray crystallographic data analyses.
View Article and Find Full Text PDFSpicatulides A-G (-), seven new phenolic-monoterpenoid hybrid molecules, along with two known compounds, and , were isolated and identified from . Compound represents an unprecedented skeleton featuring an aryl-fused 2-oxabicyclo[4.3.
View Article and Find Full Text PDFA chemical investigation on the aerial parts of Euphorbia neriifolia led to the identification of thirteen undescribed diterpenoids, phorneroids A-M, including ent-abietane (A-D), ent-kaurane (E-G), ent-atisane (H-K), and ent-isopimarane (L and M) types, together with three known compounds. Phorneroid A represents the first example of 8-spiro-fused 9,10-seco-ent-abietane diterpenoid lactone featuring a unique 6/5/6/5 spirocyclic framework. Biological assays showed that some of the compounds displayed moderate cytotoxicity against two human tumor cell lines, A549 and HL-60.
View Article and Find Full Text PDFEighteen new limonoids, including eight methyl angolensates (-) and 10 cipadesins (-), were isolated from the leaves of . Their structures were characterized by means of spectroscopic data analyses, single-crystal X-ray diffraction, and quantum chemistry computational methods. The C-6 configurations in those compounds possessing a C-6 hydroxy group were all assigned as regardless of the magnitude of , and the C-2' configuration in those bearing a 2-methylbutyryl residue was defined by single-crystal X-ray diffraction and NMR data.
View Article and Find Full Text PDFThe suadimins A-C (-) from are the first example of monoterpenoid quinoline alkaloid dimers featuring an unprecedented carbon skeleton. Their structures and absolute configurations were established on the basis of extensive spectroscopic analyses, electric circular dichroism (ECD), and X-ray crystallography. Suadimin A showed significant antimycobacterial activity in vitro with an MIC of 6.
View Article and Find Full Text PDFSeventeen new 17- nor-cephalotane-type diterpenoids, fortalpinoids A-Q (1-17), were isolated from the seeds of Cephalotaxus fortunei var. alpine. Compound 12 represents the first 17- nor-cephalotane-type diterpenoid featuring an 8-oxabicyclo[3.
View Article and Find Full Text PDFChemical investigation of an EtOH extract of the twigs and leaves of Croton damayeshu afforded 10 new tigliane diterpenoids, crodamoids A-J (1-10), along with five known compounds. Their structures were elucidated by physical data analysis. Compounds 8, 9, and 15 displayed cytotoxic effects against two human tumor cell lines, A549 and HL-60 (IC: 0.
View Article and Find Full Text PDFCapitulactones A-C, three unprecedented 9-norlignans featuring a unique 3,5-dihydrofuro[2,3- d]oxepin-7(2 H)-one scaffold, were isolated from the roots of Curculigo capitulata. Their structures with absolute configurations were unambiguously established by a combination of spectroscopic data, ECD analysis, and total synthesis. Biomimetic total syntheses of three pairs of the corresponding enantiomers were achieved in 9-10 steps with overall yields of 14.
View Article and Find Full Text PDFUrceoloids A (1) and B (2), two C steroids with a rearranged new carbon skeleton by featuring a very unique spiro[4.4]nona-3,6,8-triene system, and a biosynthetically related known steroid (3) were isolated from Urceola quintaretii. Their structures were completely established by a combined method.
View Article and Find Full Text PDFFour indole alkaloids, alstonlarsines A-D (1-4), were isolated from Alstonia scholaris and structurally characterized. Compound 1 possesses a new carbon skeleton with a cage-shaped 9-azatricyclo[4.3.
View Article and Find Full Text PDFThree dimeric sesquiterpenoids (1-3), fortunoid A (1) possessing a new carbon skeleton of rearranged lindenane dimer and fortunoids B (2) and C (3) representing the first example of the dimers of a lindenane and a eudesmane sesquiterpene, were isolated from Chloranthus fortunei. Their structures with absolute configurations were established by spectroscopic data and electric circular dichroism analysis. Their biosynthetic origins were also proposed.
View Article and Find Full Text PDFInspired by the discovery of the antimalarial drug artemisinin from a traditional Chinese medicine (TCM), a natural product library of 44 lindenane-type sesquiterpenoids was assessed for activities against the Dd2 chloroquine-resistant strain of the malaria parasite Plasmodium falciparum. These compounds were mainly isolated from plants of the Chloranthus genus, many species of which are named "Sikuaiwa" in TCM and have long been used to treat malaria. The compounds consisted of 41 sesquiterpenoid dimers and three monomers, including the 12 new dimers 1-12 isolated from Chloranthus fortunei.
View Article and Find Full Text PDFThree new ring B-seco limonoids, ciliatonoids A-C (1-3), were isolated from Toona ciliate and structurally characterized by spectroscopic data, X-ray crystallography, and electronic circular dichroism analysis. Ciliatonoids A and B feature an unprecedented limonoid architecture, while ciliatonoid C belongs to a rare class of limonoids. Biological evaluation showed that compound 3 exhibited modest activities against the tested tumor cell lines.
View Article and Find Full Text PDFNine new conjugates of sesquiterpenoids and acylphloroglucinols, named eucarobustols A-I (1-9), as well as 11 known analogues were isolated from the leaves of Eucalyptus robusta. The sesquiterpenoid motifs furnishing the new conjugates included four structural types of aristolane (1 and 2), guaiane (3), eudesmane (4), and aromadendrane (5-9) moieties. Compounds 1 and 2 were found to represent the first examples of conjugates of aristolane and acylphloroglucinol units.
View Article and Find Full Text PDFFour limonoids, cipacinoids A-D (1-4), with spirocyclic skeletons were isolated from Cipadessa cinerascens. It is particularly notable that compounds 1-3 had a 17S-configuration for the first time in the limonoid family. Their structures with absolute configurations were assigned by spectroscopic data, X-ray crystallography, and CD analysis.
View Article and Find Full Text PDFWorld J Microbiol Biotechnol
May 2015
The richness, phylogeny and composition of archaeal community associated with the roots of common reed (Phragmites australis) growing in the Beijing Cuihu Wetland, China was investigated using a 16S rDNA library. In total, 235 individual sequences were collected, and a phylogenetic analysis revealed that 69.4 and 11.
View Article and Find Full Text PDFIvorenolide B (1), an unprecedented 17-membered macrolide featuring conjugated acetylenic bonds and four chiral centers, was isolated from Khaya ivorensis. The structure of 1 was fully determined by spectroscopic analysis and total syntheses of its four most possible stereoisomers. Compound 1 showed significant immunosuppressive activity.
View Article and Find Full Text PDFJ Asian Nat Prod Res
January 2014
Four new triterpenoids, 2-O-acetyl-3-O-(4'-O-acetyl)-α-l-arabinopyranosylmaslinic acid (1), 2-O-acetyl-3-O-(3'-O-acetyl)-α-l-arabinopyranosylmaslinic acid (2), 2-O-acetyl-3-O-(3',4'-O-diacetyl)-α-l-arabinopyranosylmaslinic acid (3), and 3-O-(3'-O-acetyl)-α-l-arabinopyranosyloleanolic acid (4), together with six known triterpenoids, 3-O-(4'-O-acetyl)-α-l-arabinopyranosyloleanolic acid (5), maslinic acid (6), 2-O-acetylmaslinic acid (7), 3-O-acetylmaslinic acid (8), betulinic acid (9), and 2α-hydroxy-3β-O-acetylbetulinic acid (10), were isolated from the EtOAc extract of Garcinia hanburyi resin. Their structures were elucidated by analysis of the spectroscopic data and chemical methods.
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