Maryse Bon

New polymer and latex prepared by vinyl polymerization of derivatives of norbornene catalyzed by PdCl2, or PdCl2(TPPTS)2 in water

Abstract We developed a new method of preparation of latex by polymerization of norbornene in aqueous emulsion with SDS, catalyzed by PdCl2. The preparation of small sized latex has been also extended to latex bearing functional groups as alcohol or sugar residues. Two types of catalysts were used: PdCl2 and PdCl2(TPPTS)2. The latex were characterized by light scattering and electron microscopic examination.

Three furano-diterpenes from the bark of Croton campestris

Abstract Three furano-diterpenes have been isolated from the dichloromethane extract of Croton campestris St Hil. roots. Their structures have been established by spectroscopic methods. The compounds were named velamone (ent-15,16-epoxy-2-oxo-3,13(16),14-clerodatrien), velamolone (ent-15,16-epoxy-20-hydroxy-2-oxo-3,13(16),14-clerodatrien) and velamolone acetate (ent-15,16-epoxy-20-acetoxy-2-oxo-3,13(16),14-clerodatrien).

A New Iridoid Glucoside from African Avicennia Germinans

Abstract A new iridoid glucoside, namely 2′(4′′- hydroxycinnamoyl) mussaenosidic acid, has been isolated from the leaves of Avicennia germinans (Gabon) along with 2′-caffeoyl mussaenosidic acid. The structure of the new compound was established by spectroscopic methods.

Megastigmane and Iridoid glucosides from Avicennia Germinans: Two Isomeric Forms of an Iridoid

Abstract The iridoid 2′-coumaroyl mussaenosidic acid, isolated from Avicennia germinans (Avicenniaceae), was analysed by NMR and molecular modeling: two isomeric forms were confirmed. In addition, the known compound 1 (6S, 9R) roseoside was isolated for the first time from this species of Avicennia.

Etude en spectrographie i.r. du vibrateur (Pv)NH dans quelques phosphoranes dérivés d'hydrazides

Abstract The absorption band due to the NH stretching vibration has been studied in spiro- or monocyclicphosphoranes derived from hydrazides and containing the PNHN system. The results suggest a large degree of delocalization of the nitrogen lone pair towards phosphorus. The acidity of the NH proton appears to be strongly dependent upon the electronegativities of the atoms of groups bound to phosphorus. The J[PN(X)H] spin coupling constant is approximatively twice as large for X = N as for X = C.