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The synthesis, with asymmetric induction, of chiral hexacovalent phosphorus anions, allows a polarimetric kinetic study of epimerization or racemization mechanism of these compounds which is shown to be irregular (acid catalyzed).

Different aspects of the reactivity of the diphosphene are presented: reactivity of the lone pair and/or reactivity of the double bond.

The reaction of α-branched aldehydes with diethyl 1-carbomethoxyethyl phosphonate 1b in THF/nBuLi at low temperature leads stereoselectively to Z α-methyl α,β-unsaturated esters. From a linear aldehyde, the reaction is less stereoselective, while from α,β-unsaturated ones, the E isomers are predominantly formed in good yields. From diphenyl 1-carbomethoxyethyl phosphine oxide 2b, E α-methyl α,β-unsaturated esters are stereoselectively formed either in DMF/tBuOK or in phase transfer conditions, whatever the starting aldehyde is, also in good yields. This reagent can thus advantageously replace the corresponding P-ylid. In all cases, the reaction conditions are determined so that by-products formation is minimized.

Diphosphiranes 3a - 3f are obtained by action of diazo derivatives and carbenes on the trans-diphosphene 1 . The structures are elucidated by spectroscopic methods. In all cases the cycloaddition reaction is stereoselective.

This paper deals with the synthesis of N α -(β-naphthylsulfonylaminoglycyl)-argininamide compounds and the results of a pharmacological study ( in vitro and in vivo ). No thrombin inhibition was obtained with N α -arylsulfonyl-aminoalkyl-(4-amidinophenyl)-alaninamide compounds in which the 4-amidinophenylalanyl residue was substituted by an arginyl residue.

The Wittig-Horner reaction from diethyl cyanomethyl phosphonate 1a and aldehydes is seldom highly stereoselective1. The use of diiscpropyl cyanomethyl phosphonate 1b has been recently proposed to improve the stereoselectivity of the reaction towards the E-α, β- unsatured nitriles 2E2.

C19H14NO2S3P. monoclinic, C2/c, a=20.238 (10), b=14.345 (8) and c=15.472 (6) A, β=120.11 (5)°, V=3886 (4) A3, Z=8, M=415.5 g, dc=1.42 Mg · m−3. The structure was solved by direct methods and refined by full-matrix least-squares calculations to R=0.048. The stability of the first model of the “O-phosphobiotine” structure is understood on the ground of the large through space distance between the phosphorus and the nitrogen atoms, preventing intramolecular rearrangement to the more stable N-phosphorylated form.

The functionalized diphosphiranes 1 a–c, in presence of Lewis acid, undergo two kinds of reaction:the ring opening leading to the phosphenium-phosphonium ion 2a–c obtained according to an electrocyclic reaction and the fragmentation giving phosphaalkene 3a–c and phosphonium ion 4. The deprotonation reaction of 2a–c in hexane leads to phosphino-phosphaalkenes 6a–c.

Hybrid molecules ‘cationic metalloporphyrin–intercalators’ have been synthesized which have a high affinity for double-stranded DNA and are able to cleave it at low concentrations; compound (2), an efficient bleomycin model based on a cationic metalloporphyrin, is cytotoxic towards murine leukaemia cells L1210 in vitro; iron and zinc analogues of (2) are less active, despite having the same affinity for nucleic acids.

Diphosphiranes 3a - 3f are obtained by action of diazo derivatives and carbenes on the trans-diphosphene 1 . The structures are elucidated by spectroscopic methods. In all cases the cycloaddition reaction is stereoselective.

The 3,3-dihalogeno-1,2-diphosphiranes 1(a–b) and its photochemical isomers, the 2,3-dihalogeno-diphosphapropenes 8(a–b) lead to the 1,3-diphosphaallene 4 by action the methyllithium. The anionic ring opening mechanism appears most likely.

The synthesis of hybrid “metalloporphyrin-ellipticine” molecules is reported. These molecules are based on 9-methoxyellipticine and [5-(4-hydroxyphenyl)-10,15,20-tris (4-tolyl)]porphyrin linked by a ten-bond chain, −(CH2)4-CO-NH-(CH2)3−, between the hydroxyl group of the porphyrin and the pyridine nitrogen of the pyrido-carbazole. These molecules have been metallated with manganese, iron or zinc salts.

The 3,3-dihalogeno-1,2-diphosphiranes 1(a–b) and its photochemical isomers, the 2,3-dihalogeno-diphosphapropenes 8(a–b) lead to the 1,3-diphosphaallene 4 by action the methyllithium. The anionic ring opening mechanism appears most likely.