Triterpene glycosides of plants of the family Caryophyllaceae

In this review, tables of 25 glycosides are given and the previously unknown structures of 11 of them are established. Characteristic features of the glycosides of the family Caryophyllaceae are considered. Methods are shown for isolating the glycosides and, using acanthophylloside B — a compound having carbohydrate chains of complex structure — as example, methods of determining their structures are demonstrated.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 417–433, July–August, 1981. Original article submitted May 6, 1981.     

Xanes for Pd and Pt in square and octahedral chloride complexes

Inorganic Chemistry Institute, Siberian Branch, Academy of Sciences of the USSR. Catalysis Institute, Siberian Branch, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 29, No. 2, pp. 68–76, March–April, 1988     

Triterpene glycosides ofHedera helix II. Determination of the structure of glycoside L-6d from common ivy leaves

A new hederagenin pentaoside — glycoside L-6d — has been isolated from the leaves of common ivyHedera helix L., fam. Araliaceae, and its structure has been determined by using various NMR-spectroscopic methods. Glycoside L-6d is hederagenin 3-O-[O-α-L-rhamnopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl-(1→4)-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranoside.     

The first optically active organometallic porphyrin:meso-tetrakis[(1S)-2-methylcymantrenyl] porphine

Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 959–961, May, 1994.The present work has been financially supported by the Russian Foundation for Basic Research (Project 93-03-5827) and the Russian State Scientific and Technical Program Ecologically Safe Processes in Chemistry and Chemical Technology.     

Carbohydrates ofAlium. VIII. Polysaccharides ofAllium coeruleum

The group carbohydrate composition of the bulbs ofAllium coeruleum Pall. have been studied. The qualitative and quantitative compositions of the glucofructans, pectin substances, and hemicelluloses isolated have been determined and their physicochemical characteristics are reported. A general formula for the glucofructan fromA. coeruleum bulbs is given on the basis of the results of periodate oxidation, methylation, and IR, and¹³C NMR spectroscopy.Deceased.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 17–21, January–February, 1985.     

Modular,Homochiral, Porous Coordination Polymers: Rational Design,Enantioselective Guest Exchange Sorption and Ab Initio Calculations of Host–Guest Interactions

Two new, homochiral, porous metal–organic coordination polymers [Zn₂(ndc){(R)‐man}(dmf)]?3DMF and [Zn₂(bpdc){(R)‐man}(dmf)]?2DMF (ndc=2,6‐naphthalenedicarboxylate; bpdc=4,4′‐biphenyldicarboxylate; man=mandelate; dmf=N,N′‐dimethylformamide) have been synthesized by heating Zn^II nitrate, H₂ndc or H₂bpdc and chiral (R)‐mandelic acid (H₂man) in DMF. The colorless crystals were obtained and their structures were established by single‐crystal X‐ray diffraction. These isoreticular structures share the same topological features as the previously reported zinc(II) terephthalate lactate [Zn₂(bdc){(S)‐lac}(dmf)]?DMF framework, but have larger pores and opposite absolute configuration of the chiral centers. The enhanced pores size results in differing stereoselective sorption properties: the new metal–organic frameworks effectively and stereoselectively (ee up to 62 %) accommodate bulkier guest molecules (alkyl aryl sulfoxides) than the parent [Zn₂(bdc){(S)‐lac}(dmf)]?DMF, while the latter demonstrates decent enantioselectivity toward precursor of chiral anticancer drug sulforaphane, CH₃SO(CH₂)₄OH. The new homochiral porous metal–organic coordination polymers are capable of catalyzing a highly selective oxidation of bulkier sulfides (2‐NaphSMe (2‐C₁₀H₇SMe) and PhSCH₂Ph) that could not be achieved by the smaller‐pore [Zn₂(bdc){(S)‐lac}(dmf)]?DMF. The sorption of different guest molecules (both R and S isomers) into the chiral pores of [Zn₂(bdc){(S)‐lac}(dmf)]?DMF was modeled by using ab initio calculations that provided a qualitative explanation for the observed sorption enantioselectivity. The high stereo‐preference is accounted for by the presence of coordinated inner‐pore DMF molecule that forms a weak C? H???O bond between the DMF methyl group and the (S)‐PhSOCH₃ sulfinyl group.     

Synthesis of new derivatives of 3<Emphasis Type="Italic">β</Emphasis>-hydroxy18<Emphasis Type="Italic">β</Emphasis>H-olean-9,12-dien-30-oic acid

Ring A was transformed and new A-homo-4-aza- and 3-cyano-3,4-seco-olean-4-ene derivatives of 3β-hydroxy18βH-olean-9,12-dien-30-oic acid were synthesized. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 335–338, May–June, 2009.     

Excited state properties and quadratic optical nonlinearities in charged organic chromophores: theoretical analysis

As it has been found experimentally [K. Clays and B. Coe, Chem. Mater. 15, 642 (2003); B. J. Coe et al., 126, 10418 (2004)], elongation of the conjugation path length and N-arylation in stilbazolium chromophores both lead to substantial enhancement of the molecular optical nonlinearities. In the present contribution the authors perform a quantum chemical analysis of the excited state properties and quadratic nonlinear optical responses of a series of this type of dyes. Nonlinear optical responses are estimated by both finite-field and two-state model approaches that demonstrate an excellent qualitative mutual agreement. Time-dependent density functional theory calculations on the isolated cations predict redshift in the energy of the intramolecular charge transfer transition that is overestimated for cations with the longer conjugation path length. At the same time, in comparison with the Stark spectroscopy measurements the differences between the excited and ground state dipole moments are grossly underestimated for all compounds. The inclusion of solvent effect by polarizable continuum model affords a better agreement with experiment for these quantities. The authors' calculations demonstrate the crucial dependence of the electronic excitation properties on the way of the investigated compound geometry optimization. The origin of such dependence is discussed.     

Triterpene glycosides ofHedera helix III. Structure of the triterpene sulfates and their glycosides

From the leaves of English ivyHedera helix L. we have isolated the known 3-sulfates of oleanolic and echinocystic acids and their 28-O--L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl esters and the new 3-sulfate of 28-O--gentiobiosyl oleanolate — helicoside L-8a. The structures of the compounds isolated were deduced from the results of chemical transformations and NMR spectroscopy.Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 87–90, January–February, 1999.