Enhanced noscapine delivery using estrogen-receptor-targeted nanoparticles for breast cancer therapy.

Noscapine (Nos), an orally available plant-derived antitussive alkaloid, is in phase II clinical trials for cancer chemotherapy. It has extensively been shown to inhibit tumor growth in nude mice bearing human xenografts of hematopoietic, breast, lung, ovarian, brain, and prostate origin. However, high tumor-suppressive Nos dosages encumber the development of oral controlled-release formulations because of a short biological half-life (<2 h), poor absorption, low aqueous solubility, and extensive first-pass metabolism.

Pharmacophoric features of drugs with guanylurea moiety: an electronic structure analysis.

Several therapeutically important compounds contain guanylurea (GU) moiety. The appropriate tautomeric state of these species has not been explored, preliminary studies indicated that the traditional representation of this class of compounds use a high energy tautomeric state. In this work, quantum chemical studies (HF, B3LYP, MP2, G2MP2 and CBS-Q methods) were performed on the medicinally important GU based drugs so as to identify their stable tautomeric state and to understand the pharmacophoric features of these drugs.

Divalent N(I) character in 2-(thiazol-2-yl)guanidine: an electronic structure analysis.

Several medicinally important compounds carry a 2-(thiazol-2-yl)guanidine unit. These species are generally (erroneously) represented as 1-(thiazol-2-yl)guanidine species. Quantum chemical studies were performed to identify the appropriate tautomeric state of this class of compounds.

A new colorimetric chemodosimeter for Hg2+ based on charge-transfer compound of N-methylpyrrole with TCNQ.

Reaction of N-methylpyrrole and 7,7,8,8-tetracyanoquinodimethane (TCNQ) furnishes an intense blue unsymmetrical charge-transfer compound through regioselective attachment of tricyanoquinodimethane at the 2-position of N-methylpyrrole which was found to be selective chemodosimeter for Hg(2+) ions in CH(3)CN:H(2)O mixture (1:1 v/v, pH=7.0, 0.01 M HEPES, 0.

Conformational polymorphism in sulfonylurea drugs: electronic structure analysis.

Quantum chemical calculations have been performed using HF, B3LYP, and MP2 methods on the model sulfonylurea PhSO(2)NHC(=O)NHMe to understand the conformational and tautomeric preferences. The results indicate that a conformer with intramolecular hydrogen bond SLU-1 (hitherto not considered) is more stable than the conformer SLU-2 (which is generally considered) for sulfonylureas. The energy difference between these two conformers is about 4 kcal/mol in the gas phase; however, the energy differences between the two rotamers become negligible in the solvent phase.

Chiral solvating agents for cyanohydrins and carboxylic acids.

We have shown that a structure as simple as an ion pair of (R)- or (S)-mandelate and dimethylamminopyridinium ions possesses structural features that are sufficient for NMR enantiodiscrimination of cyanohydrins. Moreover, (1)H NMR data of cyanohydrins of known configuration obtained in the presence of the mandelate-dimethylaminopyridinium ion pair point to the existence of a correlation between chemical shifts and absolute configuration of cyanohydrins. Mandelate-DMAPH(+) ion pair and mandelonitrile form a 1:1 complex with an association constant of 338 M(-1) (DeltaG(0), -3.

A new chiral shift reagent for the determination of enantiomeric excess and absolute configuration in cyanohydrins.

Optically active mandelic acid in the presence of dimethylaminopyridine is an excellent chiral shift reagent for the determination of enantiomeric excess and absolute configuration in cyanohydrins.