Terpenoids of the rhizomes ofRhodiola rosea

The structures of two new monoterpene compounds isolated from the rhizomes ofRhodiola rosea L. (Crassulaceae) have been established: 3,7-dimethylocta-2,6-diene-1,4-diol (rosiridol) and 3,7-dimethylocta-2,6-diene-1,4-diol 1-O-β-D-glucopyranoside (rosiridin). Daucosterol has been isolated from the rhizomes of this plant for the first time.     

Flavonoids of the rhizomes ofRhodiola rosea. I. Tricin glucosides

Gallic acid and the flavonoid tricin (4′,5,7-trihydroxy-3′,5′-dimethoxyflavone) and its 7- and 5-O glucosides have been isolated for the first time from the rhizomes ofRhodiola rosea L. Identification was made on the basis of UV, IR, PMR, and mass spectra of the initial substances and the products of their acid hydrolysis and acetylation. The physicochemical constants, not previously given in the literature, of the 5-O-β-D-glucopyranoside have been determined.     

纳米金催化肉桂醛选择加氢制肉桂醇

α,β-不饱和醛/酮选择加氢生成不饱和醇是化学工业中一类重要反应,在精细化工生产中具有广泛应用,近年来吸引了研究者的广泛关注.该类反应因涉及不饱和官能团和碳氧双键的选择加氢而颇具挑战性:以肉桂醛选择加氢生成肉桂醇反应为例,肉桂醛分子中同时含有共轭的C=C双键和C=O双键,从热力学角度上看,C=O双键键能比C=C双键键能...     

LC/MS/MS identification of glycosides produced by biotransformation of cinnamyl alcohol in Rhodiola rosea compact callus aggregates

Cinnamyl alcohol was added to the media of compact callus aggregates (CCA) of Rhodiola rosea for stimulating the production of cinnamyl glycosides. The biotransformation reaction produced high amounts of rosin, while only a very low amount of rosavin was produced. As the consumption rate of cinnamyl alcohol was much higher than production of rosin, the aqueous methanol extracts of compact callus aggregates were studied by liquid chromatography-mass spectrometric methods and four new unexpected biotransformation products of cinnamyl alcohol were identified.     

Determination of the biologically active components of the rhizomes of Rhodiola rosea

A chromato-spectrometric method for the quantitative determination of the total cinnamyl glycosides and salidroside in the raw material of roseroot stonecrop using a standard sample of rosavin has been developed.All-Union Scientific-Research Institute of Medicinal Plants Scientific Production Combine, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 320–323, May–June, 1991.     

Hydroamination of cinnamyl alcohol using lithium amides

Hydroamination of cinnamyl alcohol is possible by reaction with lithium amides derived from primary or cyclic secondary amines.     

Chemical composition of the rhizomes of the Rhodiola rosea by the HPLC method

The component composition of extracts of the rhizomes ofRhodiola rosea has been studied by the HPLC method; the amount of rosavin has been determined and its lability on the autofermention of the raw material has been established.All-Union Scientific-Research Institute of Medicinal Plants, Scientific-Production Combine, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 188–193, March–April, 1991.     

Flavonoids of the epigeal part ofRhodiola rosea. II. Structures of new glycosides of herbacetin and of gossypetin

The structure of four new flavonol glycosides isolated from the epigeal part ofRhodiola rosea have been established: 7-O-α-L-rhamnopyranosylgossypetin (rhodiolgin), 8-O-β-D-glucopyranosyl-7-O-α-L-rhamnopyranosylgossypetin (rhodiolgidin), 8-O-β-D-glucopyranosol-7-O-α-L-rhamnopyranosylherbacetin (rhodionidin), and 3-O-β-D-glucopyranosyl-8-O-β-D-xylopyranosylherbacetin (rhodalidin). The properties of the previously undescribed incomplete methyl ethers of herbacetin and gossypetin obtained during the structural analysis of the glycosides have been studied. It has been found that diazomethane methylates the 5-OH groups in the diglycosides investigated.     

氯过氧化物酶修饰电极催化氧化肉桂醇的研究

将氯过氧化物酶(Chloroperoxidase,CPO)与双十二烷基溴化铵(DDAB)形成的类生物膜滴涂到Nation修饰的玻碳电极表面,再滴涂壳聚糖制得Chi/CPO-DDA B/Nafion/GC修饰电极.循环伏安曲线上可以观察到一对可逆的氧化还原电流峰,表明CPO与电极之间发生了直接的电子传递.该修饰电极可有效地催化O2还原为H2O2,产生的H2O2作为氧源与电极上的CPO结合进一步催化氧化肉桂醇,产物经气质联用色谱、以及红外光谱测试鉴定为肉桂醛,总的肉桂醛转化量达到80500mol/mol CPO,为高效专一获得末端醛提供了一种绿色合成方法.此外,还讨论了壳聚糖对提高修饰电极稳定性的作用.     

Chemical content of Margaretta rosea Oliv. roots. 323. Glycosides and aglycones

The roots of Margaretta rosea Oliv., subsp. rosea Bullock contain cardenolides mixed with Kedde negative ester glycosides. 6 Cardenolides were identified by paper chromatography (PC) and thin layer chromatography (TLC). Three of them were free aglycones (uzarigenin ( 1 ), corotoxigenin ( 3 ) and coroglaucigenin ( 5 ), the other three their corresponding 6-deoxy-β-D -allo-pyranosides (ascleposide ( 2 ), gofruside ( 4 ) and frugoside ( 6 ). Only two cardenolides ( 1 and 5 ) were isolated in crystalline form. The behaviour of the more polar portion of the glycoside mixture shows that D -gluco derivatives of at least 5 of the 6 cardenolides mentioned were also present. The Kedde. negative glycosides were a complicated mixture containing mainly 2,6-dideoxysugars linked to esterified polyhydroxy-pregnanes. After mild acid hydrolysis cymarose, oleandrose and digitoxose could be identified by PC and TLC. From the crude aglycone portion only one cristalline genin (M) could be isolated. This was still a mixture, but its main component according to the mass spectrum was a monobenzoyl derivative C₂₈H₃₈O₇. - A small amount of cristalline O-acetyl-β-amyrin was isolated from the least polar components.     

硼氢化钾还原肉桂醛合成肉桂醇的工艺研究

针对硼氢化钾还原肉桂醛制备肉桂醇的工艺,研究了反应物的物质的量之比、还原体系、反应时间、反应温度等因素对反应收率的影响.结果表明,在KBH4-THF-CH3CH2OH还原体系中,通过控制n(肉桂醛)∶n(硼氢化钾)=3∶1,在室温下反应1.5h,收率可达92.2%.     

Crystal structures and catalytic mechanism of the Arabidopsis cinnamyl alcohol dehydrogenases AtCAD5 and AtCAD4

The cinnamyl alcohol dehydrogenase (CAD) multigene family in planta encodes proteins catalyzing the reductions of various phenylpropenyl aldehyde derivatives in a substrate versatile manner, and whose metabolic products are the precursors of structural lignins, health-related lignans, and various other metabolites. In Arabidopsis thaliana, the two isoforms, AtCAD5 and AtCAD4, are the catalytically most active being viewed as mainly involved in the formation of guaiacyl/syringyl lignins. In this study, we determined the crystal structures of AtCAD5 in the apo-form and as a binary complex with NADP+, respectively, and modeled that of AtCAD4. Both AtCAD5 and AtCAD4 are dimers with two zinc ions per subunit and belong to the Zn-dependent medium chain dehydrogenase/reductase (MDR) superfamily, on the basis of their overall 2-domain structures and distribution of secondary structural elements. The catalytic Zn2+ ions in both enzymes are tetrahedrally coordinated, but differ from those in horse liver alcohol dehydrogenase since the carboxyl side-chain of Glu70 is ligated to Zn2+ instead of water. Using AtCAD5, site-directed mutagenesis of Glu70 to alanine resulted in loss of catalytic activity, thereby indicating that perturbation of the Zn2+ coordination was sufficient to abolish catalytic activity. The substrate-binding pockets of both AtCAD5 and AtCAD4 were also examined, and found to be significantly different and smaller compared to that of a putative aspen sinapyl alcohol dehydrogenase (SAD) and a putative yeast CAD. While the physiological roles of the aspen SAD and the yeast CAD are uncertain, they nevertheless have a high similarity in the overall 3D structures to AtCAD5 and 4. With the bona fide CAD's from various species, nine out of the twelve residues which constitute the proposed substrate-binding pocket were, however, conserved. This is provisionally considered as indicative of a characteristic fingerprint for the CAD family.     

Labdane diterpenes from the rhizomes of Hedychium coronarium

A new labdane diterpenoid, (E)-labda-8(17),12-dien-15,16-olide (1) together with eight known compounds, coronarin D (2), coronarin D methyl ether (3), coronarin D ethyl ether (4), isocoronarin D (5), coronarin B (6), labda-8(17),11,13-trien-15,16-olide (7), (E)-labda-8(17),12-diene-15,16-dial (8) and 16-hydroxylabda-8(17),11,13-trien-15,16-olide (9), are isolated from the rhizomes of Hedychium coronarium. Compounds 2-4, 5 and 9 are isolated as mixtures of C-15, C-14 and C-16 epimers, respectively. Their structures are determined on the basis of their spectroscopic data. The epimeric mixtures of 2 and 3 have not been reported before. Some of them were evaluated for their cytotoxicity.     

Isoflavonoid glycosides from the rhizomes of Iris germanica

Four isoflavone glycosides were isolated from the rhizomes of Iris germanica. Compounds 1 and 2 are new, while compounds 3 and 4 are known isoflavone glycosides. These compounds were identified as iriskashmirianin 4'-O-beta-D-glucoside (1), nigricin 4'-O-beta-D-glucoside (2), irilone 4'-O-beta-D-glucoside (3) and iridin (4). Their structures were determined with the help of spectroscopic methods.     

Phenylpropanoid glycosides from Rhodiola rosea

Rhodiola rosea L. (Golden Root) has been used for a long time as an adaptogen in Chinese traditional medicine and is reported to have many pharmacological properties. Along its known secondary metabolites tyrosol (1), salidroside (rhodioloside) (2), rosin (3), rosarin (4), rosavin (5), sachaliside 1 (6) and 4-methoxy-cinnamyl-O-beta-D-glucopyranoside (7), four compounds were isolated from aqueous methanol extract of the plant and identified as cinnamyl-(6'-O-beta-xylopyranosyl)-O-beta-glucopyranoside (8), 4-methoxy-cinnamyl-(6'-O-alpha-arabinopyranosyl)-O-beta-glucopyranoside (9), picein (10) and benzyl-O-beta-glucopyranoside (11) by UV, MS and NMR methods. Compounds 8 and 9 are new natural compounds whereas compounds 10 and 11 were isolated first time from R. rosea. Also the compounds 6 and 7 are isolated earlier only from the callus cultures of the plant but not from the differentiated plant.     

Diastereoisomeric saponins from the rhizomes of Tupistra chinensis

A pair of diastereoisomeric furostanol saponins was obtained from the n-butanol fraction of methanol extract from Tupistra chinensis rhizomes,a folk medicine of Shennongjia Forest District of Hubei Province.Their structures were determined,on the basis of chemical and spectroscopic evidences.