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Three new sulphur glycosides, raphanuside B-D (1-3), together with a known sulphur glycoside, raphanuside (4) were isolated from the decoction of the seeds of Descurainia sophia (L.) Webb ex Prantl, and the compound 4 was reported for the first time from this plant. Their structures were identified by means of UV, IR, 1D, 2D NMR (HSQC, HMBC and NOESY) and HR-ESI-MS spectroscopic data.

To study the chemical constituents of the Entada phaseoloides (L.) Merr., seeds of Entada phaseoloides were extracted with 70% ethanol at room temperature. Isolation and purification were performed by silica gel, reversed-phase silica gel column chromatography and semi-preparative HPLC. Structures of the pure compounds were established on the basis of spectral analysis. Four sulfur-containing amide compounds were isolated from the n-BuOH-soluble fraction and identified as entadamide A-beta-D-glucopyranosyl-(1-->3)-beta-D-glucopyranoside (1), entadamide A (2), entadamide A-beta-D-glucopyranoside (3) and clinacoside C (4). Compound 1 is a new compound. Compound 4 is isolated from the genus Entada for the first time.

Raphanuside (1), an unusual oxathiane-fused thioglycoside isolated from the seeds of Raphanus sativus L., was synthesized via 10 steps and in 11% overall yield., (2009 Elsevier Ltd. All rights reserved.)

Three new 1-thioglycosides namely methylthiomethyl 1-thio-beta-D-glucopyranoside (Afrostyraxthioside A), methylsulfonylmethyl 1-thio-beta-D-glucopyranoside (Afrostyraxthioside B) and methylsulfonylmethylthiomethyl 1-thio-beta-D-glucopyranoside (Afrostyraxthioside C) were isolated from the seeds of Afrostyrax lepidophyllus Mildbr. Their structures were mainly elucidated by using one- and two-dimensional NMR and mass spectroscopies and also by an efficient one-step synthesis. Moreover, Afrostyraxthiosides A, B and C constitute a new subclass of 1-thioglycosides isolated from natural sources.

The aim of this study was to optimize by micellar electrokinetic chromatography the separation of four glucosinolates, i.e. sinigrin, glucobrassicin and methoxyglucobrassicin involved in Cruciferae resistance mechanisms and glucotropaeolin used as an internal standard. The separation borate buffer which contained sodium dodecyl sulphate, tetramethylammonium hydroxide and methanol was firstly optimized by using a three variable Doehlert experimental design. The optimum concentrations found enabled, for the first time, to obtain an acceptable resolution between the two indole glucosinolates, glucobrassicin and methoxyglucobrassicin. Modifications of the method such as a capillary pre-rinse with pure borate buffer and a step change in voltage during experiment were performed to improve the resolutions between glucosinolates and to reduce the analysis time. This method was validated by a statistical analysis and showed good linearity, repeatability and reproducibility.