The ring-opening reaction of sugar 3,4-epoxides by 2,3,4,6-tetra-O-acetyl-1-thio-β-D-galactopyranose (7) as a nucleophile led to (1 → 3)- and (1 → 4)-thiodisaccharides. High regio- and diastereoselectivities were achieved in the synthesis of the per-O-acetyl derivative of the β-D-Galp-S-(1 → 4)-4-thio-α-D-Glcp-O-iPr (10). Analogues of the 4-thiolactoside 10 have been prepared, with the β-D-Galp...

Fifteen novel β-lactams bearing the N-ethyl tert-butyl carbamate group 5a-o and fifteen N-(2-aminoethyl) β-lactams 6a-o were synthesized by the ketene-imine [2+2] cycloaddition reaction (Staudinger ). The cycloaddition reaction was found to be totally diastereoselective leading exclusively to the formation of the cis-β-lactam derivatives. These newly synthesized β-lactams were evaluated for the...

Two glycosides were isolated from the n-Butanol soluble portion of the ethanolic portion of the stem and leaves part of stachytarpheta angustifolia. Their structures were elucidated as Iridoid glycoside (1) and a caffeic glycoside ester named as –β(3 1 , 4 1 dihydroxyphenyl)–ethyl-O-α-L-rhamnopyranosyl-(1-3)-β-D-(4-O-Caffeoyl) glucopyranoside (2) by spectroscopic Method.

The β-lactam ring of the title compound, C(26)H(25)ClN(2)O(4), is nearly planar (r.m.s. deviation = 0.025 Å) and the morpholine ring adopts a chair conformation. The mean plane of the β-lactam ring makes dihedral angles of 21.6 (4), 84.4 (4) and 33.7 (4)° with the two benzene rings and the phenyl ring, respectively. The conformation of the title compound is stabilized by intra-molecular C-H⋯O a...

Four new glycosides, namely 3β-norpinan-2-one 3-O-β-d-apiofuranosyl-(1→6)-β-d-glucopyranoside (1), (6Z)-3-hydroxymethyl-7-methylocta-1,6-dien-3-ol 8-O-β-d-glucopyranoside (2), (6E)-3-hydroxymethyl-7-methylocta-1,6-dien-3-ol 8-O-β-d-gluco-pyranoside (3), and 7-[(β-d-apiofuranosyl-(1→6)-β-d-glucopyranosyl)oxymethy]-8,8-dimethyl-4,8-dihydrobenzo[1,4]thiazine-3,5-dione (4), were isolated from the f...

Different plant parts of Ligusticopsis wallichiana (family: Apiaceae) are widely used as traditional medicines. Although many volatile constituents are already identified from the leaves of L. wallichiana, there is no detailed report on the nonvolatile constituents. In the present study, we aimed to isolate and identify the major chemical constituents from the leaves. Bhutkesoside A (1), falcar...

A new unusual minor triterpenoid saponin, platycoside O (1), was isolated from the 75% EtOH extract obtained from the roots of Platycodon grandiflorum, together with four known saponins: platycoside M-3 (2), platycoside J (3), platycoside F (4) and platycoside B (5). The structure of 1 was determined as 3-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl-2β,3β,16α,23-tetrahydroxyolean-12-en-24-meth...