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The synthesis of 2,2,3,3,11,11,12,12-octamethyl-1,4,7,10,13,16-hexaoxacyclooctadecane ( 2 ) from pinacol ( 3 ) by a sequence of reactions ( 3 → 4 → 5 → 6 + 5 → 2 ) involving alkylation ( 3 → 4 ), ozonolysis and reduction ( 4 → 5 ), tosylation ( 5 → 6 ), and cyclisation ( 5 + 6 → 2 ) is reported. With borane-ammonia, the octamethyl-18-crown-6 derivative 2 forms a crystalline 2:1 complex, (BH 3 NH 3 ) 2 · 2. X-Ray crystallography reveals the two guest BH 3 NH 3 molecules are hydrogen bonded in a centrosymmetric manner to the opposite faces of the host 2 , which adopts an all- gauche ( ag + a ag - a ) 3 conformation.

The cyclomalto-oligosaccharides [cyclodextrins, αCD ( 1 ), βCD ( 2 ), and γCD ( 3 )] and the pure methylated derivatives, hexakis(2,6-di- O -methyl)-αCD (DM- αCD, 4 ) and heptakis(2,6-di- O -methyl)-βCD (DM-βCD, 5 ), function as second-sphere ligands towards diammine(η 4 -cycloocta-1,5-diene)rhodium(I) hexafluorophosphate ( 8 ), ethylenediammine(η 4 -cycloocta-1,5-diene)rhodium(I) hexafluorophosphate ( 9 ), and diammine(1,1-cyclobutanedicarboxylato)platinum(II) ( 11 , carboplatin). The transition metal complexes are included inside the cavities of the CDs both in aqueous solution ( 1 H-m.m.r. data) and in the solid state (X-ray data). In the crystals of the 1:1 adducts 8 -αCD and 11 -αCD, the transition metal complexes have their organic ligands inserted into the cavity of 1 and their ammine ligands hydrogen-bonded to secondary hydroxyl groups on the rim. The ammine ligands of 8 are displaced in the presence of either αCD or DM-αCD, but 9 is stable. Although 8 and 9 also form adducts with βCD, 11 is specific in forming a 1:1 adduct with αCD in aqueous solution. The standard enthalpy (−25.3 kJ.mol −1 ) and entropy (−42 J.K −1 .mol −1 ) changes for the “reaction” between 11 and αCD indicate that adduct formation is an enthalpy driven process. The greatly increased solubility (from 50 to 240m m ) of 11 in aqueous solutions of αCD, and its encapsulation by αCD in the solid state, could find applications in the use of carboplatin in cancer chemotherapy.

The seeds of 161 species of legumes, representing 78 genera, were examined by chromatographic methods for canavanine content. The results are supplemented by data, variously collected, by other authors, to yield a total of 219 investigated species representing 109 genera. Of these, 68 species belonging to 32 genera have canavanine in their seeds.Canavanine has not been found in the subfamilies Mimosoideae or Caesalpinioideae. In the subfamily Papilionoideae it has not been found in the tribes Podalyrieae and Sophoreae. At least one species from each of the other tribes produces canavanine. In three genera, some species produce canavanine while others do not.These data are presumed to be of taxonomic significance and have been interpreted as support for chromosomal information indicating that the tribes Mimosoideae and Caesalpinioideae diverged relatively early from the "stem" line which is now represented by the Papilionoideae.

Formation d'un compose d'addition entre le trans-[Pt (PMe 3 )Cl 2 (NH 3 )] et la β-cyclodextrin, le coordinat PMe 3 hydrophobe s'inserant dans l'etroite ouverture de la cyclodextrine

Microcalorimetry and 1H n.m.r. spectroscopy have established that Pt(NH3)2(CBDCA)(CBDCA = cyclobutane-1,1-dicaboxylato) and α-cylodextrin (α-CD)form a 1:1 adduct in water with a standard free energy change (–ΔG⊖) in the region of 10.4–13.0 kJ mol–1 at 22–25 °C.

Etude de coordinats avec 3 chaines polyether entre 2 noyaux benzeniques, pour les complexes tels que [Rh(cod)(NH 3 ) 2 ][PF 6 ]

In the second sphere co-ordination of a cyclobitane-1,1-dicaroxy;atiammimeplatinum(II)µ-cyclodextrin, stabilisation of the crystalline adduct is achieved by the cyclobutane ring if the guest penetrating into the cavity of the hoist and the ammine ligands on the guest participating in the formation of two(N–H ··O) hydrogen bonds with secondary hydroxy group at C(3) on neighboring α-D-glucopyranosidic units in the host.