Coumarins fromPhlojodicarpus sibiricus

Phlojodicarpin [8-(2,3-epoxy-1-hydroxy-3-methylbutyl)-7-methoxycoumarin, C₁₅H₁₆O₅, mp 143–145°C, [] _D ²⁵ -37.5°], and isophlojodicarpin [8-(1,2-epoxy-3-hydroxy-3-methylbutyl)-7-methoxycoumarin, C₁₅H₁₆O₅, mp 132–134°C, [] _D ²⁵ -102.5°] have been isolated from the epigeal part ofPhlojodicarpus sibiricus. The results of the IR, UV, PMR, and mass spectrometry of these compounds are given.Institute of Chemistry, Academy of Sciences of the Mongolian Peoples' Republic, Ulan-Bator. Irkutsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 47–49, January–February, 1981.     

Terpenoids from plants of the family Cupressaceae. I. Sesquiterpene alcohols from the needles ofMicrobiota decussata

The sesquiterpene alcohols 5S,8S-germacra-1E,6E-dien-5-ol, (+)--bisabolol, hedycaryol, and -eudesmol and also the previously undescribed alcohols thujopsan-2-ol (I) and microbiotol. Microbiotol is a tricyclic tertiary alcohol with the empirical formula C₁₅H₂₆O, mp 112–113°C, containing in its molecule four tertiary methyl groups and cyclopropane ring.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostock. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 163–169, March–April, 1981.     

Action of snake venom phospholipase A2 on analogs of phosphatidylcholine

Summary The hydrolysis by phospholipase A₂ of the following synthetic phospholipids has been investigated: 2-oleoyl-1-palmitoyl-3-sn-glycerophosphorylcholine, 4-stearoyloxybutylphosphorylcholine, 4-oleoyloxy-5-palmitoyloxypentylphosphorylcholine, and 2-(hexadecyloxycarbonyl)ethylphosphorylcholine.M. M. Shemyakin Institute of Bioorganic Chemistry, Academy of Sciences of the USSR. Translated from Khimiya Priorodnykh Soedinenii, No. 3, pp. 413–415, May–June, 1975.     

A peucedanol glucoside fromPhlojodicarpus turczaninovii

The new coumarin peucedanol 3--D-glucopyranoside (I), C₂₀H₂₆O₁₀·C₂H₅OH, mp 160–162°C, has been isolated from an ethanolic extract of the epigeal part ofPhlojodicarpus turczanovii growing in the Monoglian People's Republic (Gobi-Altai). The acid hydrolysis of (I) formed D-glucose and peucedanol (II), and also decursinol and marmesin. The results of IR, UV, PMR, and¹³C NMR spectroscopy are given.Institute of Chemistry, Academy of Sciences of the Mongolian People's Republic, Ulan-Bator. Irkutsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 190–192, March–April, 1985.     

Cerebrosides of the Far Eastern sponge Hymeniacidon assimilis

Cerebrosides have been isolated from chloroform-ethanol extract of the spongeHymeniacidon assimilis. Their structures have been established with the aid of¹H NMR spectroscopy, acid hydrolysis, and ozonolysis as the -galactosides of the C₁₆-, C₁₇-, and C₁₈-erythro-⁴-sphingenines of normal, iso, and anteiso structures acylated in the amino groups with C₂₁-, C₂₂-, and C₂₃--hydroxy acids. The cerebrosides fromH. assimilis differ in structure from the corresponding compounds isolated previously from sponges.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Institute of Marine Biology, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 634–639, September–October, 1989.     

Mass spectra of some sesquiterpene lactones of the eudesmane series with a C1-OH group

Summary The fragmentation of some C₁-OH eudesmanolides has been studied with the aid of an isotopic label and high-resolution mass spectrometry. It has been shown that the most characteristic fragmentation is that with the cleavage of the C₁-C₁₀ and C₄-C₅ bonds. The sesquiterpene lactone arabsin has also been assigned to the C₁-OH eudesmanolides and this has been confirmed by its conversion into anhydroarabsin — an ,-unsaturated ketone.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 34–40, January–February, 1979.     

Features of the splitting out of a methyl radical from lycoctonine alkaloids under electron impact

The mass spectra of 53 alkaloids and their derivatives are considered. It is known that the presence of a C₆(OCH₃)-C₇(OH)-C₈ (OH) grouping in C₁₉-diterpene alkaloids leads to a high intensity of the (M - 15)⁺ ions at the expense of the C₆(OCH₃) group and considerably suppresses the competing processes of forming the [M - OH (OCH₃)]⁺ ions in the alkaloids and the (M - 56)⁺ ions in the anhydroxy bases. When the above-mentioned grouping is absent, the (M - 15)⁺ ions are formed mainly by the splitting out of a H₃ from a N-ethyl group.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii. No. 4, pp. 525–536, July–August, 1985.     

Proof of formation of an unstable conjugated triene on decomposition of gibberellin A3 in water

It has been shown by the methods of¹H NMR and high-performance liquid chromatography with recording of UV spectra that in aqueous solutions of gibberellin A₃, via gibberellenic acid, an unstable conjugated triene having _max 326 nm is formed which is readily converted into allogibberic acid and is isolated as a mixture (1:2) with this acid. In the¹H NMR spectrum of the triene, confirming its structure, spin-spin coupling both of the H-5 proton and of the protons of the methyl group with all the H-1, H-2, and the H-3 protons is observed. The precursor of allogibberic acid has been ascribed the structure of (–)-13-hydroxy-19,20-dinorgibberella-1,3,9,16-tetraen-7-oic acid with a conjugated 1,3,9-trienic system.Novosibirsk Institute of Organic Chemistry, Siberian Branch, USSR Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 738–743, September–October, 1988.     

13C NMR spectra of biologically active compounds. I. α-Homologs of 11-deoxyprostaglandin E1

The¹³C NMR spectra of a number of -homologs of 11-deoxyprostaglandin E₁ have been investigated and a stereochemical assignment has been made of the diasteromeric pairs of isomers with lengths of the -chain from seven to twelve carbon atoms. The most informative characteristics for the separation of the classes of epimers have been determined; these are differences in the chemical shifts of the C₁₃ and C₁₅ carbon atoms.Institute of Chemistry, Bashkir Branch, Academy of Sciences of the USSR, Ufa. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 315–319, May–June, 1985.