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 Glykoside der Samen von Dregea volubilis (L.) BENTH. ex HOOK. 2. Mitt. Isolierung weiterer Drevogenine Glykoside und Aglykone, 277. Mitteilung

A total of fifteen substances were identified through thin-layer chromatography, after mild acid hydrolysis of the chloroform extract from the seeds of Dregea volubilis (L.) BENTH . ex HOOK . Of these fifteen substances, eight (B, D, P, O; U, V, H and T) were isolated in crystalline form. Two of these were identical with the known genins drevogenin B (B) and drevogenin D (D). Drevogenin P (P) and the unknown substance O (probably a genin) were isolated for the first time. U proved to be identical with D -cymarose, V with the biose U1 obtained from Asclepias lilacina, and H with (+)-methyl-pachybioside. T was not investigated (probably a sugar derivative).     

Structure of pseudostichoposide A — The main triterpene glycoside from the holothurian Pseudostichopus trachus

A holostane oligoglycoside — pseudostichoposide A — has been isolated from the holothurianPseudostichopus trachus Sluiter, collected on the oceanic side of the island of Urup (Kurile Islands). Its structure has been established with the aid of¹³C and¹H NMR spectroscopy and partial acid hydrolysis with sulfuric acid in the presence of butanol as 3β-{O-(3-O-methyl-β-D-quinovopyransoyl-(1 → 3)-O-β-D-xylopyranosyl-(1 → 4)-O-β-D-quinovopyranosyl-(1 → 2)-[4-O-(sodium sulfato)-β-D-xylopyranosyloxy]}-holost-7-en-22-one. Its native genin, which has been called urupogenin (3β-hydroxyholost-7-en-22-one) was obtained on partial hydrolysis in the form of an individual compound. It is a new holostane derivative.     

Die Cardenolide der Samen von Mallotus paniculatus MÜLL.-ARG. (Euphorbiaceae). 2. Mitt.: Strukturbeweise. Glykoside und Aglykone, 295. Mitteilung

The structures of the following cardenolides, isolated from Mallotus paniculatus have been reported: Genin D = 11-oxo-uzarigenin ( 1 ), genin F = mallogenin = 11β-hydroxy-uzarigenin ( 3 ). Glycoside K = mallosid ( 5 ) is an L -rhamnoside of mallogenin, and glycoside L ( 21 ) is an L -rhamnoside of a new genine which we have called panogenin. Panogenin was isolated in crystalline form by the hydrolysis of panoside, and its structure was found to be that of 11β-hydroxy-coroglaucigenin ( 23 ). Glycoside N = glucopanoside ( 22 ), the predominant glycoside of the unfermented seeds, was found to contain one molecule of D -glucose bound in glycosidic form; its position was not investigated.     

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.     

The glycosides of Marsdenia erecta R. Br. I. Isolation, glycoside and aglycone. 325

Dried leaves of Marsdenia erecta R. Br. gave over 6% of a crude glycoside mixture, the main portion of which consisted of weakly polar material, soluble in ether or chloroform. By mild acid hydrolysis it yielded crude sugars and aglycones. The following four crist. sugars were isolated: D -cymarose, D -oleandrose and two bioses: pachybiose and marsectobiose (C₁₄H₂₄O₈, new). By PC. and TLC. the presence of digitoxose, canarose, thevetose and 3-O-methyl-6-deoxyallose could be demonstrated. The crude acyl-genin mixture contained β-sitosteryl-β-D -glucopyranoside and three highly hydroxylated pregnane derivatives: drevogenin-P, 17 β-marsdenin (C₂₁H₃₂O₆, new) and marsectohexol (C₂₁H₃₄O₆, new), all partly esterified with acetic, tiglic and benzoic acid. Five crist. acyl-genins (A1–A5) were isolated by chromatography, but most of them still were mixtures. After alkaline hydrolysis of the crude acyl-genins 6 acyl-free compounds were obtained. 4 of them were identical with the above mentioned substances, the other two: 17-iso-drevogenin-P and marsdenin (17 α-marsdenin) are formed from drevogenin-P and 17 β-marsdenin by isomerisation.     

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].     

3-O-Methl-6-desoxy-L-talose,Synthese und Identifizierung mit L-Acovenose. Desoxyzucker, 43. Mitteilung

3-O-methly-6-deoxy-L -talose has been synthesized starting from 1, 2–5, 6-di-O-isopropylidene-α-D -allose ( 1 ). Methylation, selective acidic hydrolysis, sodium periodate oxidation and GRIGNARD reaction with CH₃MgBr gave a mixture of the 1, 2-isopropylidene derivatives of 3-O-methyl-6-deoxy-D -allose and 3-O-methyl-6-deoxy-D -allose ( 7 ) and 3-O-methyl-6-deoxy-L -talose ( 8 ) (L -acovenose) could be obtained. Oxidation of the latter gave the corresponding crystalline lactone, which could be indentified with a sample obtained from natural L -acovenose.     

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.     

Struktur der Drebyssobiose,Lilacinobiose und Viminose: Desoxyzucker, 45. Mitteilung

The structures of the following three disaccharides, isolated from Asclepiadaceae, have been elucidated: Drebyssobiose (1) = 4–0-(3–0-methyl-6-deoxy-β-d-allopyranosyl)-d-digitoxose, lilacinobiose (7) = 4-O-(3-O-methyl-6-deoxy-β-d-glucopyranosyl)-d-cymarose, and viminose (13) = 4-O-(3-O-methyl-6-deoxy-β-d-glucopyranosyl)-d-digitoxose.     

Triterpene saponins fromThalictrum minus. II. Structure of an artefact

The acid hydrolysis of the predominating saponins isolated fromThalictrum minu? L. has led to the formation of a triterpenoid (I), which is an artefact of the native genin. The structure of (I) has been established as 22,25-epoxylanost-9(11)-ene-3β,16β,29-triol.     

Struktur der Marsectobiose. Desoxyzucker, 46. Mitteilung

Marsectobiose ( 1 ), a disaccharide isolated from Marsdenia erecta R. Br. , is shown to be 4-O-(3-O-methyl-6-deoxy-β-D-glucopyranosyl)-3-O-methyl-2, 6-dideoxy-D-arabinohexose.     

海枫藤中C21甾体苷的分离和结构测定

从萝摩科植物海枫藤[Marsdenia officinalis Tsiang et P.T.Li.]的藤茎中分离得到四个C21甾体去氧糖苷(1)～(4). 通过化学降解和波谱技术, 确定它们的化学结构依次为: 12-O-桂皮酰基-20-O-乙酰基(20S)-孕甾烷-6-烯-3β,5α,8β,12β,14β, 17β,20-庚醇 3-O-甲基-6-去氧-β-D-阿洛吡喃糖基-(1→4)-β-D-夹竹桃吡喃糖基-(1→4)-β-D-磁麻吡喃糖苷(1), 12-O-桂皮酰基-20-O-乙酰基(20S)-孕甾烷-6-烯-3β,5α,8β,12β,14β,17β,20-庚醇3-O-β-D-葡萄吡喃糖基-(1→4)-3-O-甲基-6-去氧-β-D-阿洛吡喃糖基-(1→4)-β-D-磁麻吡喃糖基-(1→4)-β-D-磁麻吡喃糖苷(2), 12-O-桂皮酰基-20-O-乙酰基(20S)-孕甾烷-6- 烯-3β,5α,8β,12β,14β,17β,20-庚醇3-O-β-D-黄夹吡喃糖基-(1→4)-β-D-磁麻吡喃糖基-(1→4)-β-D-磁麻吡喃糖苷(3), 12-O-烟酰基-肉珊瑚苷元3-O-β-D-葡萄吡喃糖基-(1→4)-3-O-甲基-6-去氧-β-D-阿洛吡喃糖基-(1→4)-β-D-夹竹桃吡喃糖基- (1→4)-β-D-磁麻吡喃糖基-(1→4)-β-D-磁麻吡喃糖苷(4). 其中1和2为新化合物, 分别命名为haifengtenoside A, haifengtenoside B, 3和4分别为已知化合物mucronatoside H 和 hainaneosides A, 系首次从该植物中分离得到.     

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.     

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.     

Curamycin—I Isolation and characterization of some hydrolysis products

From cultures of Streptomyces cura-coi, a chlorine containing glycosidic antibiotic, named curamycin, has been isolated. Curamycin on acid hydrolysis yields a crystalline product, curacin, and a mixture of monosaccharides. Curacin, which contains all of the chlorine of curamycin, is the ester of dichloroisoeverninic acid (3,5-dichloro-4-hydroxy-6-methoxy-2-methyl-benzoic acid) with a di-desoxyaldose C₆H₁₂O₄, whose structure has not as yet been established. Three other monosaccharides are present, two of which could be identified as -lyxose and 4-O-methyl- -fucose.     

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.     

Glykoside von Marsdenia erecta R. Br. 2. Mitteilung: Versuche zur Strukturbestimmung der Genine. Glykoside und Aglykone, 330. Mitteilung

Structures for the genins of the ester glycosides of Marsdenia erecta are suggested. They are based on the behaviour in alkaline hydrolysis of these ester glycosides, their NMR. and mass spectra and ORD. data. All genins are derived from three acyl-free pregnane derivatives, i.e. drevogenin-P ( 1 ), 17 β-marsdenin ( 3 ) and marsectohexol ( 7 ). The structure of 1 is known, 3 and 7 are new compounds, i.e. 3 = 3β,8β,11α,12β,14β-pentahydroxy-Δ⁵-pregnen-20-one and 7 = 3β,8β,11α,12β,14β,20ξ-hexahydroxy-Δ⁵-pregnene. Formulae 13–17 were attributed to the acyl-genins A-1, A-2, A-3, A-4 and A-5, but only two of them were pure compounds, i.e. acyl-genin A-3 = 11,12-di-O-tiglyl-17β-marsdenin ( 15 ) and acyl-genin A-5 = 11,12-di-O-acetyl-marsectohexoi ( 17 ). Acyl-genin A-1 is a mixture of the two esters 13a + 13b derived from drevogenin-P, and similarly acyl-genin A-2 is a mixture of the esters 14a + 14b derived from 17β-marsdenin. The poorly characterised acyl-genin A-4 is most probably a mixture of the esters 16a + 16b , also derived from 17β-marsdenin.     

Synthese neuer N-Vinylpyrrole

Syntheses of New N-Vinylpyrroles The reactions of pyrrolyl potassium ( 1 ) with (ethoxymethylene)malonic acid derivatives 2a–e yielded the carbanions 3a–e , which could be hydrolyzed to 4a–e , but with the exception of 4b they were not isolated, because a transformation to the N-vinylpyrroles 5a , c–e by elimination of ethanol took place; 1 reacted with 2b at 80°C to give 4b and 6 . Hydrolysis of 4b with KOH yielded 4g , which eliminated 1 mol of ethanol to form 5f , decarboxylation of which led to N-vinylpyrrole 7 . By cyclization of 5e under various conditions the pyrrolizines 8a , b are obtained, the hydrolysis of which did not give ketone 9 but only amino alcohol 10 . Some other cyclizations of 11a–c and 13 yielded the 3H-pyrrolizine derivatives 12a–c and 14 , respectively.     

Glycosides of marine invertebrates. XVI. Cucumariogenin from glycosides of the holothurianCucumaria fraudatrix

A new genin of the holostane series has been isolated by the acid hydrolysis of the glycosidic fraction of the holothurianCucumaria fraudatrix. It has been shown that this genin is the native alycone of glycoside G₁ from the same holothurian. The structure of the genin has been established as 16-acetoxyholosta-7,24-dien-3-ol.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 59–64, January–February, 1983.