Gerardianin A,a new abietane diterpenoid from Isodon lophanthoides var. gerardianus

A new abietane diterpenoid, gerardianin A (1), along with a known compound 6,7-dehydroroyleanone (2), has been isolated from the aerial parts of Isodon lophanthoides var. gerardianus [Bentham] H. Hara. The structure of 1 was determined on the basis of spectroscopic methods and X-ray single-crystal diffraction analysis.     

Two new rearranged abietane diterpenoids from tropical Isodon coetsa

Two new rearranged abietane diterpenoids, sincoetsin A (1) and sincoetsin B (2), were isolated from the aerial part of Isodon coetsa (Buth-Ham ex D.Don) Hara collected in Singapore, and their structures were determined by spectroscopic methods, especially 2D NMR techniques.     

Two new rearranged abietane diterpenoids from tropical Isodon coetsa

Two new rearranged abietane diterpenoids, sincoetsin A (1) and sincoetsin B (2), were isolated from the aerial part of Isodon coetsa (Buth-Ham ex D.Don) Hara collected in Singapore, and their structures were determined by spectroscopic methods, especially 2D NMR techniques.     

Gerardianin A, a new abietane diterpenoid from Isodon lophanthoides var. gerardianus

A new abietane diterpenoid, gerardianin A (1), along with a known compound 6,7-dehydroroyleanone (2), has been isolated from the aerial parts of Isodon lophanthoides var. gerardianus [Bentham] H. Hara. The structure of 1 was determined on the basis of spectroscopic methods and X-ray single-crystal diffraction analysis.     

A new furofuran lignan from <Emphasis Type="Italic">Isodon japonicus</Emphasis>

A new sesamin type furofuran lignan, (−)-sesamin-2,2′-diol (1), along with two known flavonoids (2 and 3) and three phenolic compounds (4–6) were isolated from the aerial parts of Isodon japonicus. The structures of these compounds were determined by analysis of spectroscopic data (1D-, 2D-NMR, HRMS and CD) and by comparison of the data with those of related metabolites.     

A new rearranged abietane diterpenoid from Clerodendrum kaichianum Hsu

A new abietane diterpenoid, (3S,16R)-12,16-epoxy-3,6,11,14,17-pentahydroxy-17(15?→?16)-abeo-5,8,11,13-abietatetraen-7-one (1), was isolated from the stems of Clerodendrum kaichianum Hsu, together with four known diterpenoids. The structures of the isolated compounds were assigned on the basis of their NMR spectra including 2D NMR techniques such as COSY, HMQC, and HMBC experiments, and were compared with those of the literature data. This new compound showed significant cytotoxicity against the HL-60 and A-549 tumor cell lines.     

A new rearranged abietane diterpenoid from Clerodendrum kaichianum Hsu

A new abietane diterpenoid, (3S,16R)-12,16-epoxy-3,6,11,14,17-pentahydroxy-17(15 → 16)-abeo-5,8,11,13-abietatetraen-7-one (1), was isolated from the stems of Clerodendrum kaichianum Hsu, together with four known diterpenoids. The structures of the isolated compounds were assigned on the basis of their NMR spectra including 2D NMR techniques such as COSY, HMQC, and HMBC experiments, and were compared with those of the literature data. This new compound showed significant cytotoxicity against the HL-60 and A-549 tumor cell lines.     

Tricalysiolide G and tricalysiols A and B: rearranged ent-kaurane-type and ent-kaurane-type diterpenoids from the leaves of Tricalysia dubia (Lindl.) Ohwi

Three rearranged ent-kaurane diterpenes with the cafestol-type framework have been isolated from the leaves of Tricalysia dubia. Two were found to be known diterpenoids, tricalysiolides B and C. Tricalysiolide B was isolated as colorless prisms in this experiment and its three-dimensional structure was determined by X-ray crystallography. The remaining diterpenoid was a new compound and was named tricalysiolide G. Two new ent-kaurane-type diterpenoids, given the trivial names tricalysiol A and tricalysiol B, were also isolated. The structures of the new compounds were elucidated from spectroscopic evidence.     

A new chromone glycoside from <Emphasis Type="Italic">Rhododendron spinuliferum</Emphasis>

A new chromone glycoside, 3,5,7-trihydroxylchromone-3-O-alpha-L-arabinopyranoside (1), together with quercetin (2), (+)-catechin (3), (-)-epi-catechin (4) were isolated from the aerial parts of Rhododendron spinuliferum. The structure of 1 was elucidated on the basis of spectroscopic and 2D-NMR spectral analysis. In addition, 1 exhibited mild inhibitory effect on NO production in LPS-stimulated RAW264.7 cells.     

A new homoisoflavan from Caesalpinia sappan

A new homoisoflavan, 7,3′,4′-trihydroxy-3-benzyl-2H-chromene (1), was isolated from the dried heartwood of Caesalpinia sappan L., together with seven known phenolic compounds. The structure of the new compound (1) was determined on the basis of spectroscopic analysis.     

Identification and characterization of nitric oxide synthase inSalmonella typhimurium

The presence of the nitric oxide synthase (NOS) enzyme from Salmonella typhimurium (S. typhimurium) was identified by measuring radiolabeled L-[3H]citrulline and NO, and Western blot analysis. NOS was partially purified by both Mono Q ion exchange and Superose 12HR size exclusion column chromatography, sequentially. The molecular weight of NOS was estimated to be 93.3 kDa by Western blot analysis. The enzyme showed a significant dependency on the typical NOS cofactors; an apparent Km for L-arginine of 34.7 mM and maximum activity between 37 degrees C and 43 degrees C. The activity was inhibited by NOS inhibitors such as aminoguanidine and N(G),N(G)-dimethyl-L-arginine. Taken together, partially purified NOS in S. typhimurium is assumed to be a different isoform of mammalian NOSs.     

Sesquiterpenoids from Ferula fukanensis and their inhibitory effects on nitric oxide production

Six sesquiterpene derivatives, 2,3-dihydro-7-methoxy-2S*, 3R*-dimethyl-2-[4,8-dimethyl-3(E),7-nonadienyl]furo[3,2-c]coumarin (1) and 2,3-dihydro-7-methoxy-2R*,3R*-dimethyl-2-[4,8-dimethyl-3(E),7-nonadienyl]furo[3,2-c]coumarin (2), nerolidol (3), 1-(2,4-dihydroxyphenyl)-3,7,11-trimethyl-3-ninyl-6(E),10-dodecadien-1-one (4), 1-(2,4-dihydroxyphenyl)-3,7-dimethyl-3-vinyl-8-(4-methyl-2-furyl)-6(E)-octen-1-one (5) and dshamirone (6) were isolated from an 80% aqueous methanol extract of the roots of Ferula fukanensis. The sesquiterpenoids inhibited nitric oxide (NO) production and inducible NO synthase gene expression by a murine macrophage-like cell line (RAW 264.7) [1], which was activated by lipopolysaccharide and recombinant mouse interferon-.     

Glabcensin Q-U,Five New ent-Kaurane Diterpenoids from Isodon angustifolius Var. Glabrescens

Abstract

Examination of the diterpenoid constituents of the dried leaves of Isodon angustifolius var. glabrescens led to the isolation of five new ent-kaurane diterpenoids, named as glabcensin Q-U (2–6). The structures were elucidated on the basis of spectroscopic evidences.     

A novel diterpenoid with a rearranged neoclerodane skeleton from Salvia leucantha CAV.

A new diterpenoid with a rearranged neoclerodane skeleton, spiroleucantholide (compound S1), along with four known diterpenoids—salvifaricin (compound S2), isosalvipuberulin (compound S3), salvileucantholide (compound S4), and salviandulin E (compound S5)—was isolated from the aerial parts of Salvia leucantha CAV.. The structures were established by spectroscopic methods, including the X-ray analysis of spiroleucantholide (S1).     

Two new maltol glycosides and cyanogenic glycosides from <Emphasis Type="Italic">Elsholtzia rugulosa</Emphasis> Hemsl.

Two new maltol glycosides, maltol 6′-O-β-d-apiofuranosyl-β-d-glucopyranoside and maltol 6′-O-(5-O-p-coumaroyl)-β-d-apiofuranosyl-β-d-glucopyranoside, were isolated from Elsholtzia rugulosa Hemsl. along with 11 known compounds including prunasin and amygdalin. The structures were determined on the basis of spectroscopic and chemical evidence. This is the second example of isolation of cyanogenic glycosides from Lamiaceous plants.     

Inhibitory activity of nitric oxide production in RAW 264.7 cells of daldinals A–C from the fungus Daldinia childiae and other metabolites isolated from inedible mushrooms

Three benzophenone derivatives, daldinals A–C, from the Japanese fungus Daldinia childiae were evaluated for their inhibitory activity of nitric oxide (NO) production stimulated by lipopolysaccharide (LPS) in RAW 264.7 cells. They strongly suppressed the LPS-induced production of NO with IC₅₀ values of 15.2, 4.6 and 6.4 μM, respectively. To clarify the mechanism involved, total RNA extraction, followed by reverse-transcribed, polymerase chain reaction (PCR) for inducible nitric oxide synthase (iNOS) mRNA and finally electrophoresis on agarose gel were performed. These experimental results suggest that the inhibition of the LPS-induced NO production of daldinal B is due to the inhibition of iNOS mRNA synthesis. Further, their biological activities were compared with those of other metabolites obtained during our studies on biologically active substances from inedible fungi in recent years.     

Glabcensin Q-U, five new ent-kaurane diterpenoids from Isodon angustifolius var. glabrescens

Examination of the diterpenoid constituents of the dried leaves of Isodon angustifolius var. glabrescens led to the isolation of five new ent-kaurane diterpenoids, named as glabcensin Q-U (2-6). The structures were elucidated on the basis of spectroscopic evidences.     

Free-radical-scavenging principles from Phlomis caucasica

Seven free-radical-scavenging phenolic compounds including five flavonoids, rutin (1), chrysoeriol 7-O-rutinoside (2), kaempferol 3-O-glucoside (3), chrysoeriol 7-O-glucoside (4) and naringenin (5), and two phenylethanoid glycosides, forsythoside B (6) and acteoside (7) were isolated from the methanol extract of the aerial parts of the Iranian medicinal plant Phlomis caucasica by reversed-phase preparative high-performance liquid chromatography (HPLC), and the structures of these compounds were elucidated by spectroscopic means. The free-radical-scavenging properties of 1–7 were assessed by 2,2-diphenyl-1-picryl hydrazyl (DPPH) assay. Among these compounds, forsythoside B (6) and acteoside (7) were found to be the most potent antioxidants with the RC₅₀ values of 4.97 and 4.27 μg/ml, respectively.     

A new diterpenoid from Rhizophora apiculata

A new diterpenoid, 15(S)-isopimar-7-en-1-oxo-15,16-diol (1), was isolated from the stems of mangrove plant Rhizophora apiculata. The structure of the new compound was elucidated by MS, IR, 1D, and 2D NMR techniques, including HMQC, HMBC, and NOESY correlations. In addition, seven known constituents were isolated from this plant for the first time.     

黄花倒水莲的一个新酮

Aim To study the chemical constituents of Polygala aureocauda Dunn.. Methods Chemical compounds were isolated by column chromatography and their structures were determined mainly by spectroscopic means (UV, IR, MS, ^1HNMR, ^13CNMR, HMQC, HMBC). Results Three compounds were isolated and identified as 3-hydroxy-1,4-dimethoxyxanthone (Ⅰ), 1,7-dihydroxy-2,3-methylendioxyxanthone ( Ⅱ ), 7-hydroxy-1-methoxy-2, 3-methylendioxyxanthone ( Ⅲ ). Conclusion Compounds Ⅰ -Ⅲ were isolated from Polygala aureocauda Dunn. for the first time, whereas compound Ⅰ is a new xanthone.