André Durif

SYNTHESIS AND RESOLUTION OF A CHIRAL ANALOGUE OF 2,2,6,6-TETRAMETHYLPIPERIDINE AND OF ITS CORRESPONDING NITROXIDE

Abstract The novel C2 symmetric chiral amine trans-2,6-dimethyl-2,6-diphenylpiperidine has been synthesized via two successive nitrone nucleophilic addition-oxidation sequences, followed by reduction of the intermediate nitroxide. Pure enantiomers have been obtained via resolution with mandelic acid.

Donnees cristallographiques sur quatre polyphosphates du type MII(NH4)2(PO3)4; MII = Cd,Co,Mn,Zn

MII(NH4)2(PO3)4 polyphosphates with MII = Cd, Co, Mn and Zn are monoclinic. Crystal data are given for these four new compounds. All of them have very similar tetramolecular unit cells but space group is P21n for MII = Cd, Co and Mn, and Cc orC2c for the zinc salt.

Notes. Crystal structure of bis(diphenylmethyleneamino) monosulphide, S(NCPh2)2

Crystals of the title compound are monoclinic with a= 21.323(6), b= 10.260(3), c= 10.271(3)A, β= 110.50(5)°, Z= 4, and space group P21/a. The structure has been refined to R= 0.035 for 2 325 diffractometer-measured intensities for which l > 3σ(l). The PhCNSNCPh system is largely coplanar, with the two remaining phenyl groups twisted 62.0 and 49.2° respectively out of the central CNSNC plane. Bond angles at N [121.5(2), 122.4(2)°] and S [94.7(1)°] and bond distances S–N [1.675(2), 1.676(2)A] and C–N [1.285(3), 1.288(3)A] indicate that the SN bonds are essentially single with no significant delocalisation of the lone-pair charge at nitrogen.

Synthesis of stereoisomers of 6β- and 7β-(benzylthio)-3-(p-tolyl) tropane-2-carboxylic acid methyl ester

To develop new 99mTc-labelled agents to evaluate dopamine transporters (DAT) involved in Parkinsons disease, by in vivo SPECT imaging, we have synthesized six new sulfur-containing ligands with the tropane skeleton. We have introduced the complexing sulfur atom far from the three sites of recognition by DAT of these tropane derivatives. The 6β-substituted tropinone has been obtained by a double Mannich condensation followed by the introduction of the moieties for molecular interactions at the binding site on C2 and C3, leading to the six stereoisomers.

(1R,2s,3S,6R,9S)-5,5,10,10-Tetrachloro-2-methyltricyclo[7.2.0.03,6]undec-7-ene-4,11-dione

The title compound, C(12)H(10)Cl(4)O(2), has a pseudoasymmetric centre at the methyl-substituted carbon and, in the solid state, a boat-like conformation.