Two antitumour bicyclic hexapeptides from Rubia cordifolia

Two novel antitumour bicyclic hexapeptides, named RA-XV and -XVI, were isolated from Rubia cordifolia and their structures were characterized by spectroscopic and chemical means.

Conformational recognition of RA-XII by 80S ribosomes: a differential line broadening study in 1H NMR spectroscopy

1H NMR spectroscopy has been used to demonstrate specific binding of rat 80S ribosomes to the major conformer of an antitumor bicyclic hexapeptidic glucoside, RA-XII, isolated from Rubia cordifolia, in a fast exchange process.

New antitumor bicyclic hexapeptides, RA-XI, -XII, -XIII and -XIV from Rubia cordifolia

Four new bicyclic hexapeptides, named as RA-XI, -XII, XIII and -XIV were isolated from Rubia cordifolia and showed potent antitumor activities against P-388. The structures were elucidated from spectroscopic and chemical evidences. RA-XII, XIII and -XIV were proved to be unique bicyclic hexapeptidic glucosides.

Separation of drugs by high-performance liquid chromatography with porous polymer resins

The separation of cold drugs and neuroleptics by high-performance liquid chromatogarphy with the porous polymer resin DVB-MCL-O (or 11-30-0), which is a styrene-divinylbenzene-methyl methacrylate copolymer substituted with hydroxymethyl groups, was studied. This copolymer was compared with the commercial porous polymers Hitachi gel 3011, 3011-0 and 3030. A very small theoretical plate height was obtained by using DVB-MCL-O and methanol-ammonia solution (99:1) as the stationary and mobile phases, respectively. This combination was found to be the most suitable for the rapid separation of condensed aromatic ring compounds.