Die vermutliche Struktur der Anodendroside. Glykoside und Aglykone, 331. Mitteilung

Five crystalline compounds (anodendrosides) have been isolated from Anodendron paniculatum (Roxb.)A. DC. (Apocynaceae). They represent glycosides containing unusual sugars. Tentative structures for anodendroside-A ( 155 ), ?E₁ ( 3 ), ?E₂ ( 84 ), ?F ( 144 ) and ?G ( 115 ) are now presented. These structures are based on UV., IR., but mostly on high resolution mass spectra. NMR.-spectra could be performed with A, O-acetyl-E₂ and O-acetyl-G, which are in good agreement with the suggested structures. The unusual methylendioxy group postulated in the sugar moiety of A, E₁ and E₂ was also established by chemical methods, yielding approximately 1 Mol. equiv. of formaldehyde after acid hydrolysis of anodendroside-E₂.     

Die Cardenolide von Acokanthera oppositifolia (LAM.) CODD. 3. Mitteilung . Isolierung weitere Cardenolide und teilweise Strukturaufklärung. Glykoside und Aglykone, 301. Mitt.

The presence of 19 cardenolides in the extracts from the seeds of Acokanthear oppositifolia (Lam.) CODD could be traced by means of paper chromatography. Thirteen of these cardenolides could be isolated in crystalline form, acovenoside A (= 2) being by far the major component. Of the other 12 crystalline substances, 5 could be identified with known cardenolides: 2′ = acofrioside L, 3 = acolongifloroside H, 14 = acovenoside C, 15 = acolongifloroside K, 16 = ouabain. The substances 1′, 1″, 4, 6, 7, 8 and 13 are very probably new compounds. Four of these were given trivial names and the following structures were proposed: 1″ = oppovenoside, probably 10 ; 4 = oppofrioside ( 5 ); 6 = acotaloside ( 6 ); 13 = opposide, probably 12 , cf. following publication [21]. Furthermore, the structure 8 has been proposed for acolongifloroside H.     

The glycosides of Vincetoxicum hirundinaria Medikus. I. Isolation and cleavage product (glycosides and aglycones)

The dried roots of Vincetoxicum hirundinaria MEDIKUS , collected in the lake of Garda area, yielded ca. 6% of a crude glycoside mixture, of which 5,16% consisted of relatively weakly polar material. After mild acid hydrolysis of the latter, 7 sugars could be identified through paper and thin layer chromatography, and paper electrophoresis. Of these D -cymarose, L -diginose, D -digitoxose, and a small amount of lilacinobiose could be isolated in crystalline form. Of the other three sugars, D -oleandrose was characterised as a crystalline derivative, whereas boivinose and canarose could only be identified through paper and thin layer chromatography, and paper electrophoresis. Four crystalline genins (B, D, E, G) and a glycoside (F) were isolated from the genin extract. Of these, D was very unstable and therefore thus was not further investigated. B, E, and F were shown to be 15-oxasteroids, a type of steroids so far not found in nature. Very probably, G also represents a 15-oxasteroid. The four substances B, E, G, and F were given the following trivial names: B = anhydrohirundigenin, E = hirundigenin, G = vincetogenin, and F = hirundoside-A. F is an oleandroside of anhydrohirundigenin. The structures of hirundigenin and anhydrohirundigenin have already been elucidated [35].     

The pregnane derivatives of the seeds from Dregea abyssinica (Hochst.) K. Schum. (Asclepiadacea). I. Isolation

The seeds of Dregea abyssinica (HOCHST .) K. Schum. are very rich in glycosides. These consist of a complicated mixture of ester glycosides, cardenolides are absent. All these glycosides are derived from only the two known pregnane derivatives drevogenin P and Drevogenin D. In the glycosides the latter are esterified with different acids (acetic, isovaleric, α-hydroxyisovaleric and tiglic acid) and glycosidically linked to different 2-deoxy-sugars which in part carry 3-O-methyl-6-deoxy-D-allose and terminal D-glucose. After mild acidic hydrolysis 5 crystalline sugars and 6 crystalline aglycones could be isolated. The sugars were identified as D-cymarose, asclepobiose, pachybiose, drebyssobiose and «sugar T» (formerly found in Dregea volubilis). The following aglycones were obtained: drevogenin A, drevogenin B, and four new compounds called drebyssogenin F, G, J and K. The latter was a mixture of two components (K1 and K2). From the original mixture four genuine glycosides could be isolated (the drebyssosides 1, 2, 3 and 4). Of these the drebyssosides 1 and 3 were obtained crystalline, drebyssoside 2 in amorphous but pure form and drebyssoside 4 as a mixture of mainly two closely related components. The probable structures of the new substances (drebyssobiose, sugar T, the four drebyssogenins and the four drebyssosides) are reported in the following publication.     

Die Glykoside der Wurzeln von Glossostelma carsoni (N. E. BR.) BULLOCK. Glykoside und Aglykone, 297. Mitteilung

Pentacyclic triterpenes, sterols, cardenolides and pregnane derivatives could be identified in extracts from roots of Glossostelma carsoni (N.E. BR .) Bullock. From the first group, the following substances could be isolated in crystalline form: β-amyrin, lupeol, their 3-O-acetyl derivatives, and 3-O-isovaleryl-β-amyrin. The sterols were isolated in the form of two mixed but crystalline fractions. The less polar fraction was shown to be a mixture of β-sitosterol, campesterol, stigmasterol, and cholesterol (stereoisomers are not excluded); the more polar fraction is probably a mixture of monohydroxy derivatives of the four above mentioned sterols.     

Die Cardenolide und Pregnan-Glykoside der Wurzeln von Asclepias lilacina WEIMARCK. I. Isolierungen Glykoside und Aglykone, 290. Mitteilung

The dried roots of Asclepias lilacina contain ca. 14% glykosides, in which both cardenolides and ester glycosides of pregnane derivatives are present, the latter predominating. Uzarigenin, coroglaucigenin, and their corresponding glycosides ascleposide and frugoside, resp., were shown to be present; of these four, uzarigenin was isolated in crystalline form. The ester glycosides, some of which could be isolated in a crystalline state, are predominantly composed of the aglycones 20-O-acetyl-12-O-benzoyl-sarcostin and 12,20-di-O-benzoyl-sarcostin, besides which esters of desacetyl-metaplexigenin, lineolon, and dihydrosarcostin are also present. These aglycones are mostly attached to various trisaccharides which are composed of at least two 2-deoxy-sugar residues. Mild acid hydrolysis gave, besides the genins, 7 sugars, namely cymarose, oleandrose, digitoxose, 3-O-methyl-6-deoxy-D-allose (U3), as well as 3 unknown sugars U1, U2 and U5 which are probably disaccharides. U1 and U2 were isolated in crystalline form; they are isomeric and have been named asclepobiose and lilacinobiose; they are probably composed of units similar to those in the isomeric pachybiose.     

Die Cardenolide der Samen von Mansonia altissima,A. CHEV. Glykoside und Aglykone, 286. Mitt.

The seeds of Mansonia altissima A. Chev. were found to contain ca. 1% cardiac glycosides. A total of 30 substances has been traced by paper chromatography, of which only 8 (E, K, O, P, Q, R, S, and T) were present in amounts large enough to be traced without prior enrichment of the extracts. These substances could be isolated either in pure form or as enriched mixtures. Substances E, K, O, and S were obtained in crystalline form. Apart from these substances a large amount of a mixture (N) was obtained comprising 7 components. The substances E (mansonin) and O (strophallosid) could be identified with known cardenolides. The structure of O was known; the structures of E and K (strophothevosid) are reported in the following publication. The structures of the other isolated and enriched substances (P, Q, R, S, and T) were only partially elucidated.     

金丝矮陀陀植物中甾体生物碱的分离与化学结构

最近,我们研究了云南产的金丝矮陀陀植物中的甾体生物碱。对植物样品的乙醇提取物作了系统分离,从中得到22个甾体生物碱,     

Aurasperone F--a new member of the naphtho-gamma-pyrone class isolated from a cultured microfungus, Aspergillus niger C-433

A novel dimeric naphtho-gamma-pyrone, named aurasperone F (1), was isolated from the fermentation broth of the culture extracts of Aspergillus niger C-433, isolated from grapes, along with the known compounds fonsecin (2), aurasperone B (3), aurasperone C (4), aurasperone D (5) and aurasperone E (6). The chemical structure of the new natural product was established by extensive one- and two-dimensional NMR spectroscopic studies (1H, 13C, COSY, HMQC, 1D NOE spectra), as well as on the UV, MS and IR spectral analysis.     

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.     

The anti-HBsAg (human type B hepatitis, surface antigen) and anti-HBeAg (human type B hepatitis, e antigen) C18 dibenzocyclooctadiene lignans from Kadsura matsudai and Schizandra arisanensis

The C(18) dibenzocyclooctadiene lignans including three novel schizanrin F (1), G (2), H (3), along with the known kadsurarin (4), were isolated from Kadsura matsudai. A new C(19) homolignan named schiarisanrin E (5), together with the known C(18) lignans, gomisin B (6), G (7) and (+)-gomisin K(3) (8) were obtained from Schizandra arisanensis. Gomisin B, G and (+)-gomisin K(3) showed moderate to strong activity for antihepatitis in anti-HBsAg (human type B hepatitis, surface antigen) and/or anti-HBeAg (human type B hepatitis, e antigen) tests. The structural elucidations of new compounds 1-3 and 5 were based on two-dimensional (2D) NMR techniques including COSY, HMQC, HMBC, NOESY and CD spectra. Preliminary structure-activity relationship studies for these isolated lignans are also discussed.     

Two new compounds,Talaromycin A and B,isolated from an endophytic fungus,Talaromyces aurantiacus

Abstract

Two new compounds Talaromycin A (1) and Talaromycin B (2) were isolated from a liquid culture of Talaromyces aurantiacus. The structures of 1 and 2 were elucidated by IR, MS, 1D and 2D NMR spectra and comparison of the experimental and calculated electronic circular dichroism spectra. Additional known compounds (3–6) were also isolated. These compounds were tested for monoamine oxidase, acetylcholinesterase and PI3K inhibitory activity, but showed only weak activity.     

Experiments on the intermediate structure of cardenolides F, H, I, T and U from Glossostelma carsoni (N.E. Br.) Bullock

Physical data and a few chemical reactions have been used to try to elucidate some of the structural features of a few cardenolides which are present in small quantities in the roots of Glossostelma carsoni (N.E. BR .) BULLOCK . The glycoside F is probably a derivative of xysmalogenin-β-D -sarmentoside, whereas fermentative degradation of glycoside U yielded the genin H which was identified through paper chromatography. The genins H, I and T are possibly O-acetyl-cardenolides which, however, do not correspond to any known compounds.     

人面果树皮中口 山 酮 化合物及其DPPH自由基的清除活性

从人面果乙酸乙酯提取物中分离出5个新的口 山 酮 化合物garcinenone A (1), B (3), C (4), D (7) and E (8)和7个已知化合物,其结构经过波谱技术,特别是2D-NMR技术来鉴定。Jacareubin (2), 1,4,6-trihydroxy-5-methoxy-7-(3-methyl-2-buteny1)xanthone (6), subeliptenone B (11) 和symphoxanthone (12)为首次从该植物中分离出来。在DPPH自由基的清除活性实验中,所有的化合物都显示抗氧化活性,其IC50的值在 6.0-23.2 mM。结果表明人面果是潜在的有前景的天然抗氧化剂。     

Cytotoxic Naphtho‐γ‐pyrones from the Mangrove Endophytic Fungus Aspergillus tubingensis (GX1‐5E)

Four new dimeric naphtho‐γ‐pyrones, named rubasperone D ( 1 ), rubasperone E ( 2 ), rubasperone F ( 3 ), and its atropisomer rubasperone G ( 4 ), together with four known monomeric naphtho‐γ‐pyrones, TMC 256 A1 ( 5 ), rubrofusarin B ( 6 ), fonsecin ( 7 ), and flavasperone ( 8 ), were isolated from the mangrove endophytic fungus Aspergillus tubingensis (GX1‐5E) cultivated in solid rice medium. Their structures were elucidated by spectroscopic methods, including IR, 1D‐ and 2D‐NMR, and MS. In the in vitro cytotoxicity assays, 5 displayed inhibitory activities against tumor cell lines of MCF‐7, MDA‐MB‐435, Hep3B, Huh7, SNB19, and U87 MG with IC₅₀ values between 19.92 and 47.98 μM . Compounds 1, 6 , and 8 also showed mild cytotoxic activity.     

Die Glykoside der Samen von Stapelia gigantea N. E. Br. Glykoside und Aglykone, 275. Mitteilung

The seeds of Stapelia gigantea are very rich in ester glycosides (ca. 5,9%). Mild acid hydrolysis gave a mixture of sugars which, after paper chromatography and electrophoresis, was found to be probably composed of cymarose, oleandrose, digitoxose, arabino-2,6-dideoxyhexose (= canarose) and pachybiose. The mixture of the raw genins gave after alkaline hydrolysis a mixture of about nine deacyl genins (C, D, E, F1, F2, F3, G, H, J); the acids split off during hydrolysis were not identified. The nine deacyl genins are probably closely related pregnane derivatives. The main component (E), C₂₁H₃₀O₄, was obtained in crystalline state, and was named stapelogenin. Its probable structure is reported in the following publication.     

Four new prenylated flavonoids from the roots of Cudrania tricuspidata

Four new prenylated flavonoids, cudraflavanones E‐F (1–2) and cudraflavones F‐G (6–7), together with eight known compounds were isolated from the roots of Cudrania tricuspidata. The structures of new compounds were elucidated on the basis of extensive spectroscopic analyses, including 1D and 2D NMR, HRESIMS and CD. Copyright © 2013 John Wiley & Sons, Ltd.     

The glycosides of the leaves from Isoplexis isabelliana (Webb) Masf

The isolation, characterisation and chemical investigation of the cardiac glycosides of the dried leaves of Isoplexis isabelliana (WEBB ) MASF . are described. 7 glucosides B, D, E, J (monoside), K, M, and 1 (monoside) could be obtained in homogenous form, 3 others were mixtures (“A” = A₁ + A₂, “C” = C₁ + C₂, and “G” = G + K). The substances B (gluco-evatromonoside), D (cheiroside A), E (digitoxigenin-glucosido-6-deoxyglucoside), J (digitoxigenin glucoside), and M (digitalinum verum) could be identified with known substances. The new glycosides are derived from 3 genins: digitoxigenin, uzarigenin, and xysmalogenin, which are directly bound to one of the following sugars: 6-deoxyglucose, 2-O-acetyl-6-deoxy-D -glucose, 2,6-dideoxy-D -arabinohexose (= D -canarose), and 2,6-dideoxy-D -ribohexose (= D -digitoxose), terminated by a glucose unit. –Canarobiose, a new crystalline disaccharide of D -glucose and D -canarose, has also been obtained. –Apart from these cardiac glycosides 3 C₂₁-steroids have been isolated (in addition to the 2 known genins γ-digiprogenin and purpnigenin), and their structures elucidated. The presence of 2 sapogenins has been detected.     

A new phenolic glycoside and two new monoterpenoid furocoumarins from Aurantii Fructus Immaturus

A new phenolic glycoside, citrauranoside A (1), and two new monoterpenoid furocoumarins, citraurancoumarin A (2) and citraurancoumarin B (3), along with four known compounds (4–7) were isolated from the young fruit of Citrus aurantium L. The structures were elucidated by their comprehensive analysis including 1D, 2DNMR, IR and mass spectra.     

Stilbene derivatives from two species of Gnetaceae

Five new stilbene oligomers (gnemonols A, B and C, gnemonoside E and gnetal) were isolated together with 2b-hydroxyampelopsin F and gnetin E from Gnetum gnemon and G. gnemonoides. The structures of the compounds were elucidated on the basis of spectral evidence.