FeF-mediated tandem annulation: a highly efficient one-pot synthesis of functionalized N-methyl-3-nitro-4H-pyrimido [2, 1-b] [1, 3] benzothiazole-2-amine derivatives under neat conditions.

A straight forward and highly efficient one-pot annulation of 2-aminobenzothiazole, (E)-N-methyl-1-(methylthio)-2-nitroethenamine, and aldehydes in the presence of FeF is described. Diverse functionalized N-methyl-3-nitro-4H-pyrimido [2, 1-b] [1, 3] benzothiazole-2-amine derivatives were obtained with excellent yields under neat conditions. The one-pot annulation was shown to be valid for the synthesis of highly functionalized derivatives of N-methyl-3-nitro-4H-pyrimido [2, 1-b] [1, 3] benzothiazole-2-amine from readily accessible substrates.

Preparation of -Phase Poly(vinylidene fluoride) Films on Aluminum Substrate with the Addition of Hydrated Metal Salts.

Poly(vinylidene fluoride) (PVDF) is one of the most studied polymers that exhibits piezoelectric and ferroelectric properties. PVDF crystallizes into four different forms, namely , , , and phases. Generally, the nonpolar phase, as a replacement for the polar phase with the most superior ferroelectric and piezoelectric properties, is formed from the precursor melt and solution.

Novel ionophores with 2n-crown-n topology: anion sensing via pure aliphatic C-H···anion hydrogen bonding.

A series of novel coronands having a 2n-crown-n topology based on trioxane (6-crown-3) derivatives are designed and characterized. These neutral hosts can sense anions through pure aliphatic C-H hydrogen bonding (HB) in condensed phases due to the unusual topology of 2n-crown-n. C-H bonds are strongly polarized by two adjacent oxygen atoms in this scaffold.

Dihydrogen phosphate as a hydrogen-bonding donor element: anion receptors based on acylhydrazone.

Chromogenic anion receptors based on acylhydrazone are designed and synthesized. UV-vis and (1)H NMR titration showed that receptors 1 and 2 are selective receptors for dihydrogen phosphate (H2PO4(-)). Both showed strong association constants with H2PO4(-) even in polar solvents.

Synthesis and biological evaluation of 3-aminopyrrolidine derivatives as CC chemokine receptor 2 antagonists.

Novel 3-aminopyrrolidine derivatives were synthesized and evaluated for their antagonistic activity against human chemokine receptor 2. Structure-activity studies on 3-aminopyrrolidine incorporating heteroatomic carbocycle moieties led to piperidine compound 19, and piperazine compounds 42, 47 and 49 as highly potent hCCR2 antagonists.

Application of a rapid and selective method for the simultaneous determination of carebastine and pseudoephedrine in human plasma by liquid chromatography-electrospray mass spectrometry for bioequivalence study in Korean subjects.

We describe a simple, rapid and sensitive high-performance liquid chromatography-electrospray ionization tandem mass spectrometric method that was developed for the simultaneous determination of carebastine and pseudoephedrine in human plasma using cisapride as an internal standard. Acquisition was performed in multiple-reaction monitoring mode by monitoring the transitions: m/z 500.43 > 167.

Quinoline derivative KB3-1 potentiates paclitaxel induced cytotoxicity and cycle arrest via multidrug resistance reversal in MES-SA/DX5 cancer cells.

Aims: The resistance to chemotherapeutic drugs is a major problem for successful cancer treatment. Multidrug resistance (MDR) phenotype is characterized by over-expression of P-glycoprotein (P-gp) on the cancer cell plasma membrane that extrudes drugs out of the cells. Therefore, novel MDR reversal agents are desirable for combination therapy to reduce MDR and enhance anti-tumor activity.

Participation of benzene hydrogen bonding upon anion binding.

A m-xylene-bridged imidazolium receptor, 1, has been designed and synthesized. The receptor 1 utilizes two imidazole (C-H)(+)- - -anion hydrogen bonds and one benzene hydrogen- - -anion hydrogen bond. The major driving force of complexation between the receptor 1 and anions comes from two imidazole (C-H)(+)- - -anion hydrogen bonds.

New fluorescent chemosensors for silver ion.

New fluorescent chemosensors, 1,8-bis(pyrazolylmethyl)anthracene and 9,10-bis(pyrazolylmethyl)anthracene, were synthesized. The 1,8-isomer showed selective fluorescent quenching effects with Ag(I) and Cu(II). On the other hand, the 9,10-isomer displayed a selective fluorescent quenching effect only with Ag(I).