Proanthocyanidins ofPolygonum coriarium III. Structures of proanthocyanidins T1 and T2

The roots ofPolygonum coriarum have yielded two oligomeric proanthocyanidins, T1 and T2, and their structures have been established: 3-O-galloyl-7-O-[O-(6-O-galloyl)--D-glucopyranosyl]-(–)-epigallocatechin-(4-8)-(–)-epicatechin-(4-8)-(–)-epicatechin-(4-8)-(–)-epigallocatechin 3-O-gallate (T1) and (–)-epicatechin-(4-8)-[3-O-galloyl-(–)-epigallocatechin]-(4-8)-(–)-epicatechin-(4-8)-(+)-catechin (T2).The material of this paper were presented at the IInd International Symposium on the Chemistry of Natural Compounds (SCNC, Eskisehir, Turkey, October 22–24, 1996).Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 588–593, July–August, 1977.     

Proanthocyanidins ofPolygonum coriarium. IV. Structures of proanthocyanidins T3 and T4

Two oligomeric proanthocyanidins have been isolated from the roots ofPolygonum coriarium. By a study of their physical properties and spectral characteristics and analysis of the results of chemical transformations, the chemical structures of these compounds have been established as: (–)-epicatechin-77[O--D-glucopyranosyl]₃ O-⊃-D-glucopyranosyl (m-trigallolyl)-[(4-6)-(–)-epigallocatechin]₂-(4-6)-(–)-epigallocatechin—T3; and (–)-epicatechin-3-O-galloyl-7-[O--D-glucopyranosyl]₃O--D-glucopyranosyl galloyl-[(4-6)-(–)-epicatechin]₄-(4-6)-(–)-epigallocatechin — T4.The materials of this paper were presented at the IInd International Symposium on the Chemistry of Natural Compounds (SCNC), Eskiehir, Turkey, October 22–24, 1966).Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 707–713, September–October, 1997.     

Proanthocyanidins ofPolygonum corarium. II

Eight proanthocyanidins have been isolated from the roots ofPolygonum coriarum. The structures of two dimers, two trimers, including an acylglycosylated one, a tetramer, and three oligomers have been determined. All the compounds isolated were polymers and copolymers of (-)epigallocatechin, (-)epigallocatechin gallate and (-)epicatechin with C-4β→C-8 interflavan bonds.     

Proanthocyanidins ofPolygonum corarium. II

Eight proanthocyanidins have been isolated from the roots ofPolygonum coriarum. The structures of two dimers, two trimers, including an acylglycosylated one, a tetramer, and three oligomers have been determined. All the compounds isolated were polymers and copolymers of (-)epigallocatechin, (-)epigallocatechin gallate and (-)epicatechin with C-4C-8 interflavan bonds.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. 2, pp. 233–244, March–April, 1994.     

Proanthocyanidins of Rhodiola semenovii

The structures of two compounds previously isolated fromRhodiola semenovii, rhodokhinoside (I) and rhodikhim (II), have been established.     

Proanthocyanidins of Rhodiola semenovii

The structures of two compounds previously isolated fromRhodiola semenovii, rhodokhinoside (I) and rhodikhim (II), have been established.Institute of the Chemistry of Plant Substances, Uzbek. Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 771–777, November–December, 1991.     

Proanthocyanidins ofZiziphus jujuba

The catechin and proanthocyanidin compositions of the leaves and bark ofZiziphus jujuba have been studied over the vegetation periods. This has led to the isolation of 16 compounds, including 8 monomeric catechins — (–)-epiafzelechin, (–)-epicatechin, (–)-epigallocatechin, (–)-epicatechin gallate, (–)-epigal-locatechin gallate, (+)-catechin, (+)-catechin gallate, and (+)-gallocatechin; 4 dimeric proanthocyanidins — (–)-epiafzelechin-(4-8)-(–)-epicatechin, proanthocyanidin B-2, (–)-epicatechin-(4-8)-(–)-epigallocatechin, and (–)-epiafzelechin-(4-8)-(–)-epigallocatechin; and 4 oligomeric proanthocyanidins consisting of epiafzelechin, epigallocatechin, catechin, and epicatechin with different degrees of polymerization. Their structures have been established by a study of PMR and¹³C NMR spectra and the products of chemical transformation.The materials of this paper were presented at the Second International Symposium on the Chemistry of Natural Compounds (SCNC, Eskiehir, Turkey, October 22–24, 1996).Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 221–231, March–April, 1997.