G. L. Lemiére

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The synthesis of four novel compounds, (i) [(11-{[2-(3-nitrophenyl)-4-oxo-1,3-thiazolidin-3-yl]amino}-11-oxoundecyl)sulfanyl]acetic acid (4), (ii) N-[5-methyl-2-(3-nitrophenyl)-4-oxo-1,3-thiazolidin-3-yl]undec-10-enamide (5), (iii) 2-[(11-{[5-methyl-2-(3-nitrophenyl)-4-oxo-1,3-thiazolidin-3-yl]amino}-11-oxoundecyl)sulfanyl]propanoic acid (6) and (iv)(More)
On the basis of the original lead neocryptolepine or 5-methyl-5H-indolo[2,3-b]quinoline, an alkaloid from Cryptolepis sanguinolenta, derivatives were prepared using a biradical cyclization methodology. Starting from easily accessible educts, this approach allowed the synthesis of hitherto unknown compounds with a varied substitution pattern. As a result of(More)
Neocryptolepine, a minor alkaloid of Cryptolepis sanguinolenta, was investigated as a lead for new antiplasmodial agents, because of its lower cytotoxicity than cryptolepine, the major alkaloid. Synthetic 2- or 3-substituted neocryptolepine derivatives were evaluated for their biological activity. In addition to the antiplasmodial activity (Plasmodium(More)
3',4'-Di-O-benzyl-3-O-methylquercetin (2), the precursor in the synthesis of an important antivirally active flavone 3-O-methylquercetin (1), was regioselectively alkylated at the 7-OH position by a series of 1,omega-dihaloalkanes and omega-bromoalkanols. Dimerization of the flavone had to be avoided by applying strict reaction conditions. Subsequent(More)
In addition to quercetin, hyperoside, rutin, vitexin, 2″-O-rhamnosylvitexin, (4″'-O-acetyl)-2″-O-rhamno-sylvitexin, epicatechin, procyanidin B-5, proanthocyanidin A-2, procyanidin B-2 and procyanidin C-1, which were reported before in Crataegus sinaica (Rosaceae), three more flavonoids were isolated from the same plant, i.e. (+)-taxifolin,(More)
A series of synthetic dihydrobenzofuran lignans and related benzofurans were evaluated for their cytotoxicity in a screening panel consisting of various human tumour cell lines, and for their antiprotozoal activity against L. donovani (axenic amastigotes), chloroquine resistant Plasmodium falciparum (strain K1), Trypanosoma brucei rhodesiense and T. cruzi,(More)
A set of regioisomeric 2-substituted pyridazin-3(2H)-ones containing a 3-oxo-3-phenylprop-1-en-1-yl fragment at either position 4, 5 or 6 and 2-substituted pyridazin-3(2H)-ones containing the same fragment both at positions 4 and 5 have been synthesized and evaluated as antiplatelet agents. The study allows the identification of a new highly potent platelet(More)
The antiprotozoal activities of three naturally occurring isomeric indoloquinoline alkaloids, i.e., cryptolepine (1), neocryptolepine (2), and isocryptolepine (3), and two dimeric indoloquinoline alkaloids, cryptoquindoline (6) and biscryptolepine (7), originally obtained from the plant Cryptolepis sanguinolenta, were compared with those of a new synthetic(More)
A series of synthetic dihydrobenzofuran lignans, obtained by biomimetic oxidative dimerization of caffeic or ferulic acid methyl ester followed by derivatization reactions, was tested for its antiangiogenic activity in the CAM (chorioallantoic membrane) assay. The dimerization product of caffeic acid methyl ester (2a) (methyl(More)
Indoloquinoline alkaloids represent an important class of antimalarial, antibacterial and antiviral compounds. They have been shown to bind to DNA via intercalation preferentially at GC-rich sequences containing nonalternating CC sites. The stability of complexes formed with biological macromolecules depends on noncovalent binding. In the present study, the(More)