A new aromatic compound 3,4,5-trimethoxyphenyl-1-O-(4-sulfo)-β-D-glucopyranoside (1), in addition to two triterpenoid saponins (chebuloside II, arjunoglucoside II), two triterpenes (arjunolic acid and 3-betulinic acid) and sitosterol-3-O-β-D-glucopyranoside have been isolated from the barks of Terminalia catappa. Their structures have been established on
Four new oleanane-type saponins 3-O-α-L-rhamnopyranosyl-(1 → 4)-β-D-glucuronopyranosyl-22-O-β,β-dimethylacryloylA1-barrigenol (1), 3-O-α-L-rhamnopyranosyl-(1 → 4)-β-D-glucuronopyranosyl-22-O-angeloylA1-barrigenol (2), 3-O-β-D-glucopyranosyl-(1 → 2)-[β-D-glucopyranosyl-(1 → 6)]-β-D-glucopyranosyl-21,22,28-O-triacetyl-(3β,21β,22α)-olean-12-en-16-one (3), and 3-O-β-D-glucopyranosyl-(1 → 2)-glucopyranosyl-22-O-β-D-glucopyranosylsteganogenin (4), along with the known 3-O-β-D-galactopyranosyl-(1 → 2)-[α-L-arabinopyranosyl-(1 → 3)]-β-D-glucuronopyranosyl-22-O-angeloylA1-barrigenol and 3-O-α-L-rhamnopyranosyl-(1 → 4)-β-D-glucuronopyranosyloleanolic acid, were isolated from
The syntheses of homogeneous penicillamine disulfide cross-linked polypeptides are reported. Dodecapeptides containing N-terminal, C-terminal, or N- and C-terminal Pen were serially ligated into 36 amino acid polypeptides linked through Cys-Pen, Pen-Cys or Pen-Pen disulfide bonds. Critical to the syntheses was
Phytochemical investigations of the roots of Spergularia marginata had led to the isolation of four previously undescribed triterpenoid saponins, a known one and one spinasterol glycoside. Their structures were established by extensive NMR and mass spectroscopic techniques as 3-O-β-D-glucuronopyranosyl echinocystic
The phytochemical study of two cultivars of Pittosporum tenuifolium Banks & Sol. ex Gaertn, "variegatum" and "gold star", led to the isolation of eight oleanane-type glycosides: seven previously undescribed and a known one. Their aglycons are oxygenated oleanane derivatives as
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