Control of the regioselectivity for new fluorinated amphiphilic cyclodextrins: synthesis of di- and tetra(6-deoxy-6-alkylthio)- and 6-(perfluoroalkypropanethio)-alpha-cyclodextrin derivatives.
Twelve new di- and tetraderivatized alpha-cyclodextrin molecules having either alkylthio and perfluoroalkylpropanethio functions at the primary face have been synthesized by using the procedure of Sinay for di-O-debenzylation of perbenzylated alpha-cyclodextrins. A new strategy of protection/deprotection has been developed for introducing the lipophilic chains. The coupling reaction involves the reaction between the appropriate alpha-cyclodextin derivative, regioselectively modified at C-6 positions by a good leaving group (O-mesityl for disubstituted or iodine for tetrasubstituted derivatives), with the thioalkyl or the thioperfluoroakylpropane chains. These nucleophilic reagents are obtained from the in situ basic hydrolysis of the alkylisothiouronium bromides or perfluoalkylropropane and the isothiouronium iodides. These multistep reactions give the desired amphiphilic alpha-cyclodextrins in good overall yields of 33% to 58%.
Bertino-Ghera
Bernard
B
Universite Lyon 1, ICBMS UMR CNRS 5246, LCO2, Batiment Raulin, 43, bd du 11 novembre 1918, Villeurbanne, France.
Perret
Florent
F
Fenet
Bernard
B
Parrot-Lopez
Hélène
H
D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002247:Carbon Isotopes; D003505:Cyclodextrins / Q000138:chemical synthesis* / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy / Q000379:methods / Q000592:standards; D008969:Molecular Sequence Data; D012015:Reference Standards; D013237:Stereoisomerism
D002247:Carbon Isotopes; D003505:Cyclodextrins