Synthesis of Some Novel Phenyl Substituted Oxothiazolidin- 1’’,3’’,4’’-thiadiazolo-[3’,4’-b]thiazoline of 3β-Substituted Cholestane

Three title compounds 4a—4c have been synthesized by the cyclodehydration of 1’-benzylidine-4’-(3β-substituted-5α-cholestane-6-yl)thiosemicarbazones 2a—2c with thioglycolic acid followed by the treatment with cold conc. H2SO4 in dioxane. The compounds 2a—2c were prepared by condensation of 3β-substituted-5α-cholestan- 6-one-thiosemicarbazones 1a—1c with benzaldehyde. These thiosemicarbazones 1a—1c were obtained by the reaction of corresponding 3β-substituted-5α-cholestan-6-ones with thiosemicarbazide in the presence of few drops of conc. HCl in methanol. The structures of the products have been established on the basis of their elemental, analytical and spectral data.     

A Luminescent Tb(Ⅲ)-4,4’,4’’-nitrilotribenzoate Compound with a Three-dimensional Structure

A coordination polymer of [Tb(ntb)]n(1) based on 4,4’,4’’-nitrilotribenzoate ligand(ntb3–) was synthesized. Compound 1 crystallizes in monoclinic system, space group C2/c with a = 13.7318(4), b = 27.5628(9), c = 5.4046(2) ?, β = 111.142(3)°, V = 1907.88(12) ?3, Z = 4, C21H12NO6Tb, Mr = 533.24, Dc = 1.856 g/cm3, μ = 3.745 mm–1, F(000) = 1032, the final R = 0.0184 and wR = 0.0456 for 1883 observed reflections with Ⅰ > 2s(Ⅰ). In compound 1, the eight-coordinated Tb(III) atoms are bridged by carboxylate groups of ntb3– ligands to generate a one-dimensional Tb-carboxylate chain, which is further linked by the ntb3– ligands to form a three-dimensional structure. Compound 1 exhibits characteristic Tb(Ⅲ) luminescent emissions in the solid state.     

Synthesis of Hydroxylated Sterols(Ⅱ)--Synthesis of 24-Methylenecholest-4-en-3β,6α-diol

In our study on the soft coral,Alcyonium patagonicum,a new hydroxylated sterol,24-methylenecholest-4-en-3β,6α-diol(1) exhibiting a potent activity to murine leukemia cells(IC50=1 μg/mL) has been isolated[1] and synthesized[2,3].As a part of our studies on the relationship between the chemical structure and the biological activity of the hydroxylated sterols,the synthesis of 24-methylenecholest-4-en-3β,6α-diol(2) is reported here.     

Synthesis and in vitro activities on anti-platelet aggregation of N,N’-di(2-substituted-phenyl)-4-methoxyisophthalamides and benzene- 1,3-disulfonamides

On the propose of searching for the SAR and obtaining novel antiplatelet aggregating drugs,we have described the synthesis procedure and the activities in vitro on antiplatelet aggregation of two series of derivatives,which contain both 18 N.N’-di(2- substitutedphenyl)-4-methoxyisophthalamides(2a-2r) of the 2 series and nine N,N’-di(2-substitutedphenyl)-4-methoxybenzene- 1,3-disulfonamides(3a-3i) of the 3 series.The results showed that three compounds 2e,2i and 3g emerged as significant activities of antiplatelet aggregation,superior to two reference drugs picotamide and aspirin,and eight compounds 2j,2k,21,2o,2p,2q,2r and 3i merely superior to picotamide.The preliminary SAR shows that it is favorable for the 2 series to increase the activities via the steric hindrance substituents attached to the two side chain benzene rings at 2-positions.And the arylamides of the 2 series have better the activity values than the arylsulfonamides of the 3 series respective except for 3b and 3g.On the contrary,electrostatic factors would not contribute evidently to the activities of the two series.The structures of 15 compounds newly synthesized have been established by MS and ~1H NMR and been first reported in this paper.     

Structure determination of glycopeptide of β-momorcharin

The structure of the N-linked oligosaccharide chain of β-momorcharin, a ribosome-inactivating protein from the seeds of Momordica charantia Linn (Cucurbitaceae), was determined. A glycopeptide liberated by pronase digestion of the glycoprotein was subjected to amino acid and neutral carbohydrate analysis to establish the composition of amino acid and sugar residues. The sequences and glycosylation hnkages of the sugar and amino acid residues in the glycopeptide were determined as Manαl-6(XyIβ1-2)-Manβ1-4GlcNAcβ1-4(Fucαl-3)-GlcNAc-Asn-Leu by 2D-NMR spectroscopy and FAB-MS data.     

Improved preparation of (1S,3’R,4’S,5’S,6’R)-5-chloro-6-[(4-ethylphenyl)methyl]-3’,4’,5’,6’-tetrahydro-6’-(hydroxymethyl)-spiro[isobenzofuran-1(3H),2’-[2H]pyran]-3’,4’,5’-triol

A convenient approach for the preparation of(1S,3’R.4’S,5’S,6’R)-5-chloro-6-[(4-ethylphenyl)methyl]- 3’,4’,5’,6’-tetrahydro-6’-(hydroxymethyl)-spiro[isobenzofuran-1(3H),2’-[2H]pyran]-3’,4’,5’-triol is developed. The targeted compound was synthesized from 2-bromo-4-methylbenzoic acid in nine steps and the isomers of undesired ortho-products were avoided during the preparation.     

Two New Cardenolide Glycosides from Biondia hemsleyana

Two new cardenolide glycosides, biondianosides A and B, were isolated from the roots of endemic plant of Biondia hemsleyana (Warb.) Tsiang. Their structures were elucidated as periplogenin-3-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl(1→4)-β-D-cymaropyranoside (1) and 17βH-periplogenin-3-O-β-D-cymaropyranoside (2) by the spectroscopic and chemical methods.     

中药白头翁的皂素III.配基结构的研究

The structure of anemosapogenin 1 has been proved to be 3β, 23-dihydroxylup-20 (29)-en-28-oic acid on the basis of spectroscopic (IR, ^1H NMR, C-13 NMR, MS) evidences and chemical transformations, namely, the formation of acetonide 3 from 6, the acid catalysed rearrangement of 1 and 2 into 18 (α)-oleanan-28, 19β-olide derivatives 4 and 5 respectively and finally, the conversion of 7 through LiAiH4 reduction into the known compound, lup-20(29)-ene- 3β, 23, 28-triol. The third sugar component of the saponin is shown to be arabinose.     

Phenolic compounds from Anaphalis aureo-punctata

From the ethanolic extract of the whole plant of Anaphalis aureo-punctata, a new acylated flavonoid glycoside 3-O-kaempferol-3-O-acetyl-6-O-(p-coumaroyl)-β-D-glucopyranoside (1), and five known phenolic compounds 3-O-kaempferol-6- O- ( p-coumaroyl )-β-D-glucopyranoside ( 2 ), kaempferol-3- O-β-D-glucopyranoside 3,6-(4′-hydroxystyryl)-4-methoxy-2-pyrone (4), 2H-pyran-2-one, 6-[ 2-( 4-(β-D-glucopyranosyloxy ) phenyl ) ethenyl ]-4-methoxy-( E ) (5) and 4-hydroxy-3-methoxycinnamic hexacosyl ester (6) were isolated. Their structures were established by spectral methods (UV, IR, MS, 1D, 2D-NMR). The flavonoid glycosides, 1, 2 and 3 showed markedly inhibited oxidative DNA strand breaks induced by Fenton reaction and NADH/PMS in a concentration-dependent manner.     

Sesquiterpene Esters from Salvia roborowskii

Two new sesquiterpene esters,3β,6β,8α-triacetyl-4β,5α-epoxy-1-oxogermacr10(14)-ene(1)and 3β,6β,8α-triacetyl-4β,5α-epoxygermacr-1(10)-ene(2) were isolated from the whole plant of Salvia roborowskii Maxim.Their structures were elucidated by means of spectral data(2DNMR and HRMS).     

Two New C-21 Steroidal Glycosides from the Stems of Stephanotis mucronata

Two new C-21 steroidal glycosides, mucronatosides M（1） and N（2）, were isolated from the stems of Stephanotis mucronata, together with one known compound stephanoside M（3）. On the basis of chemical evidence and extensive spectroscopic methods, including one-dimensional and two-dimensional NMR, the structures of the two new compounds were identified as 12-O-tigloyl-20-O-N-methylanthraniloyl sarcoslin 3-O-β-D-glucopyranosyl-（1→4）-6- deoxy-3-O-methyl-β-D-allopyranosyl-（→4）-β-D-cymaropyranosyl-（1→4）-β-D-cymaropyranoside （1）, and 12-O- cinnamoyl-20-O-nicotinoyl（ 2OS）-pregn-6-ene-3 β,5α,8βm12 β,14β,17β,20-heptanol 3-O-β-D-glucopyranosyl-（1→4）-6- deoxy-3-O-methyl-β-D-allopyranosyl-（1→4）-β-D-cymaropyranosyl-（1→4）-β-D-cymaropyranoside （2）.     

Isoflavonoid Glycosides from the Rhizomes of Iris germanica

Five new di‐ and triglycosides, irigenin 7‐[O‐β‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐glucopyranoside] ( 1 ), 6‐hydroxygenistein 4′‐[O‐β‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐glucopyranoside] ( 2 ), nigricin 4′‐[O‐β‐D ‐glucopyanosyl‐(1→6)‐β‐D ‐glucopyranoside] ( 3 ), nigricin 4′‐[O‐β‐D ‐glucopyanosyl‐(1→2)‐O‐[α‐L ‐rhamnopyranosyl‐(1→6)]‐β‐D ‐glucopyranoside] ( 4 ), and 7‐{4′‐{[2″‐O‐(4′′′′‐acetyl‐2′′′′‐methoxyphenyl)‐β‐D ‐glucopyranosyl]oxy}‐3′‐(β‐D ‐glucopyranosyloxy)phenyl]‐9‐methoxy‐8H‐1,3‐dioxolo[4,5‐g]‐[1 benzopyran‐8‐one‐] ( 5 ), along with a known compound, nigricin 4′‐(β‐D ‐glucopyranoside) ( 6 ), were isolated from the rhizomes of Iris germanica. The structures of these compounds were established by spectroscopic methods, including 2D NMR spectroscopic techniques.     

Isolation of a New Carotenoid and Two New Carotenoid Glycosides from Curtobacterium flaccumfaciens pvar poinsettiae

An efficient method for the extraction of the carotenoids from Curtobacterium flaccumfaciens pvar poinsettiae was developed. The glucosides of C.p. 450 (=(all‐E,2R,2′R)‐2‐[4‐(β‐D ‐glucopyranosyloxy)‐3‐methylbut‐2‐enyl]‐2′‐(4‐hydroxy‐3‐methylbut‐2‐enyl)‐β, β‐carotene; 4 ) and of C.p. 473 (=(all‐E,2R,2′S)‐2‐[4‐(β‐D ‐glucopyranosyloxy)‐3‐methylbut‐2‐enyl]‐2′‐(3‐methylbut‐2‐enyl)‐3′,4′‐didehydro‐1′,2′‐dihydro‐β,ψ‐caroten‐1′‐ol; 5 ) were isolated for the first time. In addition, the hitherto unknown 3′,4′‐dihydro derivative of C.p. 450, called C.p. 460 (=(all‐E,2R,2′R)‐2‐(4‐hydroxy‐3‐methylbut‐2‐enyl)‐2′‐(3‐methylbut‐2‐enyl)‐1′,2′‐dihydro‐β,ψ‐caroten‐1′‐ol; 6 ), was identified. The structures were established by UV/VIS, CD, ¹H‐ and ¹³C‐NMR, and mass spectra.     

Replacement of Canonical DNA Nucleobases by Benzotriazole and 1,2,3‐Triazolo[4,5‐d]pyrimidine: Synthesis,Fluorescence, and Ambiguous Base Pairing

The syntheses and the fluorescence properties of 7H‐3,6‐dihydro‐1,2,3‐triazolo[4,5‐d]pyrimidin‐7‐one 2′‐deoxy‐β‐D ‐ribonucleosides (=2′‐deoxy‐8‐azainosine) 3 (N³), 15 (N²), and 16 (N¹) as well as of 1,2,3‐benzotriazole 2′‐O‐methyl‐β‐ or ‐α‐D ‐ribofuranosides 6 (N¹) and 24 (N¹) are described. Also the fluorescence properties of 1,2,3‐benzotriazole 2′‐deoxy‐β‐D ‐ribofuranosides 4 (N¹) and 5 (N²) are evaluated. From the nucleosides 3 – 6 , the phosphoramidites 19, 26a, 26b , and 28 are prepared and employed in solid‐phase oligonucleotide synthesis. In 12‐mer DNA duplexes, compound 3 shows similar ambiguous base‐pairing properties as 2′‐deoxyinosine ( 1 ), while the nucleosides 4 – 6 show strong pairing with each other and discriminate very little the four canonical DNA constituents.     

Four New Lariciresinol‐Based Lignan Glycosides from the Roots of Rhus javanica var. roxburghiana

The four new lariciresinol‐based lignan glycosides, (?)‐lariciresinol 4′‐(6″‐O‐feruloyl‐β‐D ‐glucopyranoside) ( 1 ), (?)‐lariciresinol 4′‐(4″,6″‐di‐O‐feruloyl‐β‐D ‐glucopyranoside) ( 2 ), 5,5′‐dimethoxylariciresinol 4′‐(4″,6″‐di‐O‐feruloyl)‐β‐D ‐glucopyranoside) ( 3 ), and 4‐O‐[α‐(1,2‐dihydroxyethyl)syringyl]‐5,5′‐dimethoxylariciresinol 4′‐(4″,6″‐di‐O‐feruloyl‐β‐D ‐glucopyranoside) ( 4 ), together with two known ones, lariciresinol 4′‐β‐D ‐glucopyranoside) ( 5 ) and tortoside B ( 6 ), were isolated from the BuOH extract of Rhus javanica var. roxburghiana roots, and their structures were established by means of various spectroscopic techniques.     

Seven New Phenolic Glucosides from Viburnum cylindricum

Seven new phenolic glucosides, 2′‐O‐acetylhenryoside ( 1 ), 2′,3′‐di‐O‐acetylhenryoside ( 2 ), 2′,6′‐di‐O‐acetylhenryoside ( 3 ), 2′,3′,6′‐tri‐O‐acetylhenryoside ( 4 ), 2′,3′,4′,6′‐tetra‐O‐acetylhenryoside ( 5 ), 2‐[(2,3‐di‐O‐acetyl‐β‐D ‐glucopyranosyl)oxy]‐6‐hydroxybenzoic acid ( 6 ), and 6‐hydroxy‐2‐[(2,3,4,6‐tetra‐O‐acetyl‐β‐D ‐glucopyranosyl)oxy]benzoic acid ( 7 ), were isolated from the leaves and stems of Viburnum cylindricum, along with 26 known compounds (henryoside=2‐(β‐D ‐glucopyranosyloxy)‐6‐hydroxybenzoic acid [2‐(β‐D ‐glucopyranosyloxy)phenyl]methyl ester). The structures of the new compounds were established on the basis of chemical and spectroscopic evidences.     

New Isoflavone C‐Glycosides from Pueraria lobata

Three new isoflavone C‐glycosides, along with two known isoflavone O‐glycosides, were isolated from the roots of Pueraria lobata (Willd .) Ohwi . The structures of the new compounds were elucidated as 4′,7‐dihydroxy‐3′‐methoxyisoflavone 8‐C‐[β‐d‐ glucopyranosyl‐(1→6)]‐β‐d‐ glucopyranoside ( 1 ), 4′,7‐dihydroxy‐3′‐methoxyisoflavone 8‐C‐[β‐d‐ apiofuranosyl‐(1→6)]‐β‐d‐ glucopyranoside ( 2 ), and 8‐C‐β‐d‐ glucopyranosyl‐4′,7‐dihydroxy‐3′‐methoxyisoflavone 4′‐O‐β‐d‐ glucopyranoside ( 3 ) on the basis of spectroscopic methods, especially 2D‐NMR and MS analyses. The known compounds isolated were identified by comparison of their physical and spectroscopic data with those reported in the literature.     

Thrombin Inhibitory Constituents from Duranta repens

The C‐alkylated flavonoids 3,7,4′‐trihydroxy‐3′‐(4‐hydroxy‐3‐methylbutyl)‐5,6‐dimethoxyflavone ( 1 ), 3,7‐dihydroxy‐3′‐(4‐hydroxy‐3‐methylbutyl)‐5,6,4′‐trimethoxyflavone ( 2 ) and the trans‐clerodane diterpenoids 6β‐hydroxy‐15,16‐epoxy‐5β,8β,9β,10α‐cleroda‐3,13(16),14‐trien‐18‐oic acid ( 3 ) and 2β‐hydroxy‐15,16‐epoxy‐5β,8β,9β,10α‐cleroda‐3,13(16),14‐trien‐18‐oic acid ( 4 ) were isolated from Duranta repens. Their structures and the relative configuration of 3 and 4 were determined by spectroscopic methods (¹H‐ and ¹³C‐NMR, IR, and MS) and 2D‐NMR experiments. The known flavonoid 5 is also reported for the first time from this species. The compounds 1 , 3 , and 5 showed significant enzyme‐inhibitory activity against thrombin.     

New Iridoid and Secoiridoid Glucosides from the Roots of Gentiana manshurica

One new iridoid glucoside, 4″‐O‐β‐D ‐glucosyl‐6′‐O‐(4‐O‐β‐D ‐glucosylcaffeoyl)linearoside ( 1 ), and two new secoiridoid glucosides, 6′‐O‐acetylsweroside ( 2 ) and 6′‐O‐acetyl‐3′‐O‐[3‐(β‐D ‐glucopyranosyloxy)‐2‐hydroxybenzoyl]sweroside ( 3 ), were isolated from the dried roots of Gentiana manshurica (Gentianaceae), together with 11 known ones, including one iridoid glucoside, five secoiridoid glucosides, and five triterpenes. The structures of the new compounds were determined on the basis of detailed spectroscopic analyses and acidic hydrolysis.     

Stilbenoids and Phenols in Acanthopanax brachypus

Three new stilbenoids, including α‐(3′‐O‐β‐D ‐glucopyranosyl‐5′‐methoxyphenyl)‐2‐methoxy‐3‐methylbenzofuran ( 1 ), 4‐methyl‐(E)‐resveratrol 3‐(2″‐p‐hydroxybenzoyl)‐O‐β‐D ‐glucopyranoside ( 2 ), and 5‐O‐methyl‐(E)‐resveratrol 3‐(6″‐acetyl)‐O‐β‐D ‐glucopyranoside ( 3 ), together with six known stilbenoids and phenols, acetovanillone 1‐(6′‐vanilloyl)‐O‐β‐D ‐glucopyranoside, eugenyl‐O‐β‐D ‐glucopyranoside, α‐(3′‐hydroxy‐5′‐methoxy‐2′‐methylphenyl)‐2‐hydroxybenzofuran, α‐(3′‐hydroxy‐5′‐methoxyphenyl)‐2‐hydroxybenzofuran, pinosilvin 3‐O‐β‐D ‐glucopyranoside, and (E)‐resveratrol 3‐(6″‐galloyl)‐O‐β‐D ‐glucopyranoside were isolated from the EtOH extract of the stem bark of Acanthopanax brachypus. Their structures were determined by spectral analysis including extensive 2D‐NMR spectral analyses. Compounds 2 and 3 exhibited weak cytotoxicity against human tumor A549 cell line (IC₅₀ values of 4.87 and 5.63 μM , resp.).