Triterpenoids from the leaves ofBetula costata

Summary From the unsaponifiable part of an ethereal extract of the leaves ofBetula costata four triterpenoids of the dammarane series have been isolated. For the previously unknown triterpenoids A and C the structures of dammar-24-ene-3,17,20-triol and of betulafoliene-tetraol oxide, respectively, have been proposed.Pacific Ocean Institute of Bioorganic Chemistry, Far-Eastern Scientific Center of the Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 757–762, November–December, 1976.     

Triterpenes from the leaves ofBetula ermanii

Summary From the unsaponifiable fraction of an ethereal extract of the leaves ofBetula ermanii a new triterpene of the dammarane series — 20,24-epoxydammarane-3,6,25-trol (II) — and its 6-O-acetyl derivative (I) have been isolated.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center of the Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 587–590, September–October, 1978.     

Triterpenoids from the leaves of far eastern species of the shrubby birchesBetula ovalifolia andB. middendorfii

From the unsaponifiable fraction of an ethereal extract of the leaves ofBetula ovalifolia have been isolated the new triterpene 20(S),24(R)-epoxydammarane-3,17,25-triol (V) and the corresponding monoketone at C³ (VI). The leaves ofB. middendorfii have yielded the triterpene (IX) and (X), identified as, respectively, dammar-23-ene-3,12,20(S),25-tetraol and damman-25-ene-3,12,20-(S),24-tetraol, which have been obtained previously from the leaves ofBetula platyphylla Sukatchev var.japonica.The species of birch were determined by V. I. Baranov of the Laboratory of Chemotaxonomy.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 323–329, May–June, 1981.     

Triterpenoids from the leaves ofBetula lanata

From the unsaponifiable fraction of an ethereal extract of the leaves ofBetula lanata, in addition to 3-epiocotillol (I) we have isolated a new triterpene, 20(S), 24(R)-epoxydammarane-3α,11α,25-triol (V) and also derivatives of it — the monoacetates at C-3 (II) and C-11 (III), and the monoketone at C-3 (IV). The structures of compounds (I-V) have been established on the basis of the results of physicochemical investigations.     

Triterpenoids from the leaves ofBetula costata

From the unsaponifiable part of an ethereal extract of the leaves ofBetula costata four triterpenoids of the dammarane series have been isolated. For the previously unknown triterpenoids A and C the structures of dammar-24-ene-3α,17α,20-triol and of betulafoliene-tetraol oxide, respectively, have been proposed.     

Triterpenoids from Psidium guajava leaves

Three pentacyclic triterpenoids including one new guajavanoic acid (2) and two known obtusinin (1) and goreishic acid I (3) have been isolated from the leaves of Psidium guajava. The new constituent 2 has been characterized as 2alpha-hydroxy-3beta-p-E-coumaroyloxyurs-12, 18-dien-28-oic acid through 1H-NMR and 13C-NMR (broad band and DEPT). This is the first report of isolation of compound 1 and 3 from the genus Psidium.     

Polysaccharide from the leaves ofPhytolacca americana

A polysaccharide has been isolated from the leaves ofPhytolacca americana and has been characterized. It has been established that it contains residues of galactose, arabinose, xylose, and rhamnose, in a ratio of 3:4:1:3 and also D-galacturonic acid (85–90%). The results obtained permit the polysaccharide to be assigned to the class of pectin substances.All-Union Oncologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 166–169, March–April, 1982.     

Triterpenoids of the leaves of Betula pendula from different growth sites

A comparative study has been made of the triterpene fraction of the unsaponifiable part of ethereal extracts of five samples of the leaves ofBetula pendula collected in various regions of the Soviet Union. Together with known sterols and triterpenoids, two new compounds have been isolated — 12,20(S),25-trihydroxydammar-23-en-3-one and dammar-25-ene-3,12,17,20(S),24-pentaol, the structures of which have been determined on the basis of spectral characteristics and chemical transformations.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center of the Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 179–185, March–April, 1986.     

Alkaloids from the leaves ofStrychnos icaja Baill.

From the leaves ofStrychnos icaja Baill. a further seven alkaloids have been isolated and their structures determined: 16-hydroxystrychnine (1e), 21,22-α-epoxy-4-hydroxy-3-methoxy-N-methyl-sec.-pseudostrychnine (5c), 21,22-α-epoxy-4-hydroxy-N-methyl-sec.-pseudostrychnine5a), 21,22-α-epoxy-2-methoxy-N-methyl-sec.-pseudostrychnine (5b), 21,22-α-epoxy-14-hydroxy-N-methyl-sec.-pseudostrychnine (6a), 21,22-α-epoxy-4,14-dihydroxy-N-methyl-sec.-pseudostrychnine (6b), and 14-hydroxy-N-methyl-sec.-pseudostrychnine (7). Jaminet's alkaloid B' is shown to be impure 21,22-α-epoxy-14-hydroxy-2,3-dimethoxy-N-methyl-sec.-pseudostrychnine (6c).     

Triterpenoids from Cedrela sinensis

Twenty-three new triterpenoids (1-23), all having an apotirucallane skeleton, were isolated from the seeds, leaves, and stems of Cedrela sinensis (Meliaceae). Their structures were determined by 2D NMR experiments, X-ray crystallographic analysis, and chemical methods. These triterpenoids showed a moderate cytotoxic activity against P-388 murine leukemia cells (IC₅₀ 0.26-9.9 μg/mL).     

Triterpenoids from the leaves of the siberian species of birchBetula nana andB. exilis

The compositions of the triterpene fractions of the unsaponifiable part of the ethereal extracts of the leaves ofB. nana andB. exilis have been studied. The leaves ofB. exilis have yielded a new triterpene for which the structure of 3,20(S),25-trihyproxydammar-23-ene is proposed, and a four component mixture of epimers at C-3 and C-24 of the compound 3,20(S),24-trihyproxydammar-25-ene. The composition and ratio of the components of the mixture were determined on the basis of chemical and spectral characteristics.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 352–356, May–June, 1985.     

A new steroid saponin from the leaves ofYucca aloifolia

A new steroid saponin has been isolated from the air-dry leaves ofYucca aloifolia L., and it has been shown to be (25R)-5-spirostan-3-ol O-D-glucopyranosyl-(1 2)-D-galactopyranoside. The substance melts at 302–303°C []D²⁰ –27.2, (c 1.0; CHCl₃).I. G. Kutateladze Institute of Pharmacochemistry, Academy of Sciences of the Georgian SSR, Tbilisi. Translated from Khimiya Prirodnikh Soedinenii, No. 6, pp. 744–747, November–December, 1984.     

Mass-spectrometric analysis of phytol derivatives from the leaves ofPlatanus orientalis

Products of the oxidation, polymerization, and esterification of tocopherols and esters of phytol with aliphatic acids have been identified in fractions of an alcoholic extract of shed plane leaves by means of mass-spectrometric analysis.Deceased.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, FAX (3712) 62 73 48. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 363–371, May–June, 1994.     

Two new megastigmane O-glucopyranosides from the leaves of Broussonetia papyrifera

Two new megastigmane O-glucopyranosides,named (2R,3R,5R,6S,9R)-3-hydroxy-5,6-epoxy-β-ionol-2-O-β-D-glucopyrano- side(1) and (2R,3R,5R,6S,9R)-3-hydroxyl-5,6-epoxy-acety-β-ionol-2-O-β-D-glucopyranoside(2) together with six known mega- stigmanes,were isolated from the leaves of Broussonetia papyrifera (Linn.) Vent.Their structures were established by chemical methods and spectroscopic techniques including 2D NMR.