An efficient synthetic route toward the preparation of a complete series of monosubstituted tetraalkylammonium cyclodextrin (CD) derivatives is presented. Monotosylation of native CDs (α-, β-, γ-) at position 6 gave the starting material. Reaction of monotosylate (mono-Ts-CD) with 45% aqueous trimethylamine gave CDs substituted with one cationic functional group in a single step. Derivatives eq...

Complexation of two types of dicationic bipyridium guests, paraquat derivatives and bis(N-mono-substituted bipyridine) cations, by a negatively charged carboxylato-biphen[3]arene (CBP3) in water is reported. CBP3 could strongly interact with these guests, where charge-transfer and electrostatic interactions play important roles.

BACKGROUND α-Bromination of the side chain of aromatic ketones using NBS in the presence of p-toluenesulfonic acid (p-TsOH) in acetonitrile is very common. However, regioselective bromination of bis and tris(ω-bromoacetophenones) with NBS in the presence of p-TsOH in acetonitrile under microwave irradiation is quite novel. The bis- and tris(ω-bromoacetophenones) are used in synthesis of bis and...

Mono-ureido salicylic acid derivatives form hydrogen bonded dimers that mimic the gelation behaviour of covalently linked bis(urea)s. The 5-ureido salicylic acid isomers are much more effective gelators because of the lowered conjugation and less planar geometry, resulting in stronger urea···urea α-tape hydrogen bonding interactions.

We report the synthesis of new guanylhydrazones from imidazo[2,1-b]thiazoles and of a bis-guanylhydrazone from diimidazo[1,2-a:1,2-c]pyrimidine. The compounds were tested as potential antitumor agents at the National Cancer Institute. Two derivatives are now under review by BEC: one of these was also subjected to a test for positive inotropic activity in view of a possible coanthracyclinic acti...

an electroorganic reaction for the synthesis of 7-amino-2, 4-dioxo-5-phenyl-2,3,4,5-tetrahydro-1h-pyrano[2, 3-d] pyrimidine-6-carbonitrile and ethyl-7-amino-2, 4-dioxo-5-phenyl-2,3,4,5-tetrahydro-1h-pyrano[2, 3-d] pyrimidine-6-carboxylate derivatives are described, using an electrogenerated base of the anion of malonitrile or ethylcyanoacetate. this one-pot, three-component condensation of an a...

Five known porphyrins, 5,10,15,20-tetrakis(p-tolyl)porphyrin (TTP), 5,10,15,20-tetrakis(p-bromophenyl)porphyrin (TBrPP), 5,10,15,20-tetrakis(p-aminophenyl)porphyrin (TAPP), 5,10,15-tris(tolyl)-20-mono(p-nitrophenyl)porphyrin (TrTMNP), 5,10,15-tris(tolyl)-20-mono(p-aminophenyl)porphyrin (TrTMAP), and three novel porphyrin derivatives, 5,15-di-[bis(3,4-ethylcarboxymethylenoxy)phenyl]-10,20-di(p-t...

Convenient procedure for the synthesis of corresponding pyrano[2,3-d]pyrimidine derivatives were developed via one-pot three-component reaction of aryl aldehyde derivatives, malononitrile with barbituric acids in the presence of copper (II) chloride dihydrate (CuCl2.2H2O) as highly efficient Lewis acid catalyst. This protocol has advantages such as readily and inexpensive catalyst, high reactio...