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From the pericarps of the capsules of Euscaphis japonica PAX., oleanolic, pomolic, tormentic acids and a new triterpene acid, named euscaphic acid were isolated and the structure of euscaphic acid was elucidated to be 2α, 3α, 19α-trihydroxyurs-12-en-28-oic acid by chemical and spectral evidences.

The high-molecular-weight constituents of the branched and cyclic hydrocarbon fraction of the Messel oil shale (Eocene) have been examined by high-resolution gas chromatography and combined gas chromatography/mass spectrometry. The following compounds are present: perhydrolycopene, together with one or more unsaturated analogs with the same skeleton; a series of 4-methylsteranes in higher abundance than their 4-desmethyl analogs; two series of pentacyclic triterpanes, one series based on the hopane structure, and the other based on the 17 alpha-H hopane structure; and an intact triterpene hop-17(21)-ene. Only two additional triterpanes were detected in minor concentrations - namely, 30-normoretane and a C31 triterpane based on the hopane/lupane-type skeleton. The presence of these compounds suggests a significant microbial contribution to the forming sediment.

Melissa off. L. enthalt als weitere Triterpene: Pomolsaure, drei 2-Hydroxy- und eine 20-Hydroxytiterpensaure. In der Wurzel kommen Betulinsaure, Betulin und drei 2-Hydroxytriterpensauren vor. Die Konfiguration der 2,3-Dihydroxytriterpensauren wird durch Synthese der vier isomeren 2-Hydroxyderivate von Oleanolsaure, Ursolsaure und α-Amyrin bewiesen. Further Triterpenes from Melissa officinalis L. Melissa off. contains as further triterpenes pomolic acid, three 2-hydroxy- and one 29-hydroxytriterpenic acid. The root contains betulinic acid, betulin and three 2-hydroxytriterpenic acids. The configuration of the 2,3-dihydroxytriterpenic acids was proved by synthesis of the four isomeric 2-hydroxy-derivatives of oleanolic acid, ursolic acid and α-amyrin.

The leaves of Prunus serotina and P. lusitanica contain a new triterpene, 2α,3α-dihydroxyurs-12-en-28-oic acid, isolated in form of its methyl ester. Other triterpenes present in these species are ursolic acid and ursol aldehyde. P. lusitanica also yields friedeline.

1. 1. The digestive tracts of twenty-one marine invertebrate species of different systematic and ecological positions were qualitatively tested for glycosidase content by using several synthetic and natural triterpene and steroid glycosides as substrates. 2. 2. The species Colisella sp., Tellina lutea, Mercenaria stimpsoni, Macoma sp. and Patinopecten yessoensis showed the presence of a glycosidase.

A calorimetric investigation has been made of the mesomorphic behavior for the palmitate esters for four tetracyclic triterpenes-pollinastanol, 31-norcycloartanol, cyclaoartanol, and cyclorartenol....

Gymnemic acids, the triterpene saponins from the leaves of the asclepiad vine Gymnema sylvestre, act as feeding deterrents to a caterpillar, Prodenia eridania. The effect is demonstrable with sugar-free diets, suggesting that the acids do not act, as they do in mammals, by suppressing the sweetness of sugars.

Die Massenspektren von Ginsenoside-Rg1-decaacetat und verwandte Triterpensaponin-acetate vom Dammarantyp wurden untersucht. Die von Elyakov u.a. vorgeschlagene Struktur des Panaxoside A ( = Ginsenoside-Rg1)1 wird kommentiert. Mass spectra of ginsenoside-Rg1 deca-acetate1 and the related dammaran-type triterpene saponin acetates have been studied and a comment is given on the structure of panaxoside A (=ginsenoside-Rg1) 1 proposed by Elyakov, et al .

The structure of philoside B — a gypsogenin nonaoside isolated from the roots ofGypsophila patrinii — has been established.

Robinson annelations using ethyl 3-oxo-4-pentenoic acid (Nazarov's reagent, 1)1 are an important route to α-ethoxycarbonylcyclohexenones (e.g., 2→4).1

The structure of alnuserrudiolone, a new C31-dammarane-type triterpene isolated from the male flowers of Alnus serrulatoides Call. (Betulaceae), has been elucidated to be (20s)-12β,20-dihydroxy-24-...

In den Samenkornern der Kornrade (Agrostemma githago L.) findet sich als Hauptglycosid das monodesmosidische Triterpenglycosid Githagosid (1a). Saure Hydrolyse von 1b ab liefert als Aglycon Gypsogenin und die Zucker D-Glucose, D-Xylose, D-Fucaose und L-Rhamnose, Die Struktur der Zuckerkette konnte durch Permethylierung, Identifizierung der Methylzucker, Perjodat-Oxidatin, enzymatischen Abbau und Partialhydrolyse ermittelt werden. Als Aglycon von Nebensaponinen der Kornrade wurde Quillajasaure festgestellt. Triterpenes, XXX. The Main Saponin of the Corncockle (Agrostemma githago L.) A monodesmosidic triterpene glycoside, githagosid ( 1a), the main saponin of corncockle seeds, was investigated. Acid hydrolysis of 1b yielded the aglycone gypsogenin and the sugars D-glucose, D- xylose, D-fucose, and L-rhamnose. The structure of the sugar chain was established by permethylation, identification of the resulting methyl sugars, periodate oxidation, enzymatic degradation, and partial hydrolysis. Another aglycone, quillaic acid, was identified in the residue of the minor saponins after hydrolysis.

An X-ray diffraction study has established the structure of the dibromo derivative of a new triterpene ether isolated from Salacia prinoides DC. as (IIb), a derivative of friedelane.

Flowers of Calendula officinalis were incubated with mevalonic acid doubly labelled with 14 C in position 2 and 3 H in positions 2R, 2S, 4R or 5R,S and the [ 3 H/ 14 C] ratios determined in squalene and pentacylic mono- and dihydroxy-triterpene alcohols and also in some derivatives prepared from the triterpene alcohols. 3 H atoms were located in positions 3, 12, 16, 21, 29, 30 of the ursane skeleton, positions 3, 12, 29, 30 of the lupane skeleton and positions 3, 11, 12, 18 of the oleanane skeleton. Stabilization of α- and β-Amyrins, ω-taraxasterol and lupeol occurs with the elimination of a proton from positions 12, 21 and 29 (or 30) respectively. In addition, during hydroxylation of triterpene monols to the corresponding diols a proton is substituted by the hydroxyl group.

A complex combination of carbohydrase activites has been demonstrated in the digestive tract of the inland snailE. maakii. Gel filtration on biogel P-200 enables partially purified preparations of several glycosides (including those acting on some triterpene and steroid glycosides), two laminarinases, and a pectinase—“zosterinase”—to be obtained.

The saponin from the berries of Phytolacca americana yielded one known and two new aglycones. One of the new aglycones was identified as desmethylphytolaccagenin 2 , and the other as 3β, 23-dihydroxyolean-12-ene-28, 30-dioic acid-30-methyl ester 3 .

A stereospecific method previously developed in the triterpene series for the synthesis of inotodiol (I) is shown to be equally valid in the steroid series. Addition of the appropriate Grignard reagent to (22ξ)-22,23-epoxy-6β-methoxy-3α,5α-cyclo-24-norcholane (VI) and (VII)[derived from the bromohydrins (Va–c)] furnished, after regeneration of the 5-en-3β-ol system, the title compounds in good yields, almost stereospecifically. It follows that electrophilic addition to the double bond occurs as previously defined for 24,25,26,27-tetranorlanosta-8,22-dien-3β-yl acetate, the (22S)-23-bromo-22-hydroxy- and (22R)-22-bromo-23-hydroxy-isomers being the major bromohydrins formed.

3( RS )-[2- 14 C,(4 R )-4- 3 H 1 ]-mevalonic acid has been incorporated into diploptene, hopene-I, fernene and serratene in Polypodium vulgare . The retention of six tritium atoms in fernene and of only five in hopene-I indicates that no double bond intermediates are involved in the final rearrangement in the formation of fernene.

The isolation of a new triterpene, putranjivadione, is described. By a combination of chemical and physical methods it was shown that putranjivadione is friedelane-3,7-dione (I).

The constitution VII of hydroxyhopanone, the first natural squalenoid pentacyclic triterpene, has been proved by an unequivocal partial synthesis of its dehydration product hopenone-I (XVI).

The sapogenin mixture obtained from the bark of Clerondendron serratum has been found to contain three major triterpenoid constituents, viz. oleanolic acid. queretaroic acid, and a new acid, named serratagenic acid, for which the structure 3β-hydroxy-Δ12-oleane 28,29-dioic acid has been deduced.

The molecular structure and stereochemistry of the triterpene arborinol was obtained from a three-dimensional X-ray diffraction study of 2α-bromoarborinone. The molecule is shown to be pentacyclic with a 13β, 14αtrans configuration of the methyl groups at the C/D ring junction, not previously found among pentacyclic triterpenes. The space group is P212121, with four molecules in the unit cell: a = 12·84 b = 8·68 c = 22·46 A. The value of R = (Σ|Fo| − |Fc|)/Σ|Fo| is 12·4% for 1719 observed reflections. The implications of the structure for the ferenen-group of triterpenes are discussed.

From the leaves ofEleutherococcus senticosus four glycosides of oleanolic acid have been isolated, and they have been called eleutherosides I, K, L, and M. Eleutherosides I and K are biosides whose carbohydrate chains consist of L-arabinose and L-rhamnose residues. Eleutherosides L and M are pentaosides and differ from I and K, respectively, by the fact that they contain a trisaccharide consisting of D-glucose and L-rhamnose attached by an O-acylglycosidic bond to the carboxy group. The absence of branching and of 1,3 bonds in the carbohydrate chains of the eleutherosides has been shown.

The bark ofWrightia tinctoria has been found to contain triterpenes as the major components andβ-sitosterol as a minor component. The former includedβ-amyrin, lupeol and another triterpene alcohol which seems to be new.

The biogenetic isoprene rule in its application to the triterpenes is discussed from a stereochemical standpoint. On the basis of a well defined system of arbitrary assumptions a scheme has been developed leading from squalene to the formulae of the basic representatives of all known cyclic triterpene groups - i.e. euphol, tirucallol, lupeol, taraxasterol, germanicol, β-amyrin, taraxerol, friedelin, α-amyrin, lanosterol - in their full structural and configurational detail. This result is considered to support the squalene hypothesis of the biogenesis of cyclic triterpenes.

3β-Acetoxyhexakisnordammaran-20-one (V) was prepared from hydroxyhopanone (II) through IV, VI, VII, VIII, IXc and XII. Since the total synthesis of II has already been performed, the present transformation provides the total synthesis of the basic skeleton of dammarane-type triterpene.

1. By degradation of the tetracyclic alcohol tirucallol (V) into the tricyclic compound XI and methyl L-(+)-2,6-dimethyl-oenanthate (X) it has been shown that tirucallol differs from the isomeric triterpene euphol (I) only in the configuration of carbon atom 20.

1. The structure of a new triterpene glycoside from the roots ofCalendula officianlis L. — calenduloside A—has been established as the 3-O-[O-β-D-galactopyranosyl-(1→4)-β-D-glucopyranoside] of oleanolic acid. 2. The 3-O-β-D-glucopyranoside of oleanolic acid has been isolated fromC. officialis for the first time.

The structure of gymnestrogenin, a new triterpene from the leaves of Gymnema sylvestre R. Br. (Asclepiadaceae), is proposed to be that of 3β, 16β, 21β, 23, 28-pentahydroxy-olean-12-ene.

The purpose of this short account is to present some results which cast doubt on the validity of the methods used generally for the study of phytosterol biosynthesis (though not necessarily on the validity of the conclusions arrived at). We shall accept, and not discuss, the present general framework of interpretation of sterol biosynthesis (chart 1) (see for example Goad 1970). Key intermediates, from our point of view, are squalene, squalene epoxide, and a triterpene alcohol: lanosterol in vertebrates and in fungi, cycloartenol in the green plants. The transformation squalene-squalene epoxide is an oxidative step; the transformation squalene epoxidetriterpene alcohol is the biochemical equivalent of an acidcatalysed isomerization.

From the fraction of the feebly polar saponins ofPatrinia scabiosofolia Fisch. et Link oleanolic acid, hederagenin, β-sitosterol, β-D-glucopyranoside, and hederagenin 3-α-L-arabopyranoside have been isolated. The polar fraction has yielded two triterpene glycosides. It has been established that one of them is oleanolic acid 3-O-β-D-glucopyranosyl-(1 → 4)-α-L-arabinopyranoside, and the other is hederagenin 3-O-β-D-glucopyranosyl-(1 → 4)-α-L-arabopyranoside.

A new triterpene diol isolated from the lichen Sticta billardierii is shown to have the structure 15α,22-dihydroxy-hopane.

From the rhizoma of Peltoboykinia tellimoides (MAXIM.) HARA, two triterpene acids were isolated. One of them, a new triterpene, named β-peltoboykinolic acid (I), mp 220-222°(decomp.), [α]24D+114°, has been established to be olean-12-ene-3β-ol-27-oic acid and another, named α-peltoboykinolic acid (II), mp 234-236°, [α]17D+121°, to be urs-12-ene-3β-ol-27-oic acid, which is identical with a compound derived from quinovic acid by L. Ruzicka, et al. in 1946. These are the first examples of naturally occurring triterpene acids with the only carboxyl group at C-27 of ursane and oleanane types.

The leaves ofDiospyros melanoxylon Roxb. growing in Mysore, have been shown to contain ceryl alcohol, lupeol, betulin,β-sitosterol, sequoyitol, a new triterpene alcohol, m.p. 212–13°, and a new triterpene carboxylic acid named diospyric acid, m.p. 272–74°.