Dominique Cartier

Atypical Oxidation Reaction by Thionyl Chloride: Easy Two‐Step Synthesis of N‐Alkyl‐1,4‐dithiines

Abstract Easy two‐step synthesis of a series of dithiines was performed from succinic anhydride via cyclization of the corresponding 4‐(alkylamino)‐4‐oxobutanoic acids (succinamic acids). The reaction, carried out in polar aprotic solvents, gave 4,8‐dithiine‐indacene‐1,3,5,7‐tetraones (diimides 3) via 3,7‐bis‐4,8‐dithia‐indacene‐1,5‐diones (diisoimides 2), which could be isolated. Surprisingly, in this reaction, thionyl chloride appeared as an oxidant, and this process seemed to be useful for the syntheses of S‐containing heterocyclic compounds such as 1,4‐dithiins. A mechanistic pathway was considered.

Synthesis of hexacyclic indole alkaloids related to vindolinine by sonochemical cyclization

Abstract Upon treatment with sodium in THF under sonication, 19-iodotabersonine underwent cyclization to the vindolinine ring system. The yields and ratio of the diastereomers thus obtained depended on the sonication parameters.

Cyclization of Oxindolic methylketones with acid : A rapid synthesis of (±)-aspidofractinine

The oxindolic methylketone 7 was cyclized in one step to the hexacyclic ketolactam 9 with acid. (±)-Aspidofractinine 23 was prepared by sequential reduction of 9. The model oxindolic methylketone 11, when reacted with acid, gave compounds 12 and 17a,b.

A New Stereoselective Synthesis of Acitretin (= Soriatane®, Neotigason®)

A new synthesis of acitretin via a C15+C5 route is reported. The C15 unit is the key step, involving a procedure that provides the required (all-E)-C15-aldehyde with high stereoselectivity.

A short total synthesis of (±)-19-hydroxyaspidofractinine

Abstract 3,19-Dioxoaspidofractinine 13 was prepared in two steps from 2-hydroxytryptamine, and further reduced to the title compound 6 .

Approaches towards indolic analogues of cephalotaxine via a spiro-cyclohexene strategy

Abstract Highly functionalized (dialkyloxo)indoloazepines 10 , 11 , 34 and the pyrroloazepinoindole 35 were prepared via oxidative cleavage of the corresponding spiro-cyclohexene derivative. Tetracycle 35 bears carbons and functionalities required for building the new ring system 2 .

Synthesis and transformations of a 20-deethyl 3-oxo vincadifformine.

Abstract A 20-deethyl 3-oxo vincadifformine 3 was synthesized via condensation of 2-hydroxy tryptamine with synthon 9 . It was further alkylated to the oxo-pseudovincadifformine 2 . The given relative configurations remain hypothetical.

New Synthetic Analogs of Retinoids: Synthesis of Aromatic Analogs of 9-Methylidene- and 13-Demethyl-9-methylidene-retinol, -retinal, and Ethyl 13-Demethyl-9-methylideneretinoate

Aromatic analogs of 9-methylidene and 13-demethyl-9-methylideneretinol, -retinal, and ethyl 13-demethyl-9-methylideneretinoate were synthesized via a new β-methylidene-aldehyde synthon.

Synthesis of pyrazolidinone antibacterial agents

The synthesis of monocyclic pyrazolidinones, which show moderate antibacterial activity, are described.

N-Benzene-sulfonyl-indole as terminator in a biomimetic polyene cyclization: synthesis of a pentacyclic indolosesquiterpene

Abstract Epoxide 14 was cyclized with BF 3 to the pentacyclic derivative 17 , which was further elaborated to 19 , a stereoisomer of the natural indolosesquiterpene polyveoline.