Synthesis of tetrahydrobenzimidazo[1,2-b]quinazolin-1(2H)-one and tetrahydro-1,2,4-triazolo[5,1-b]quinazolin-8(4H)-one ring systems under solvent-free conditions.

Tetraheterocyclic benzimidazo[1,2-a]quinazolin-4(1H)-one and tetrahydro-1,2,4-triazolo[5,1-b]quinazolin-8(4H)-one were synthesized in relatively high yields by the condensation reaction of an aldehyde and a cyclic beta-diketone with 2-aminobenzothiazole, 2-aminobenzimidazole or 3-amino-1,2,4-triazole without using any catalyst under solvent-free conditions.

Effect of oral naltrexone on pruritus in cholestatic patients.

AIM: To determine the efficacy and potential complications of oral naltrexone used in the treatment of pruritus in cholestatic patients and to compare them with other studies. METHODS: Thirty-four enrolled cholestatic patients complaining of pruritus were studied. In the initial phase, pruritus scores during day and night were evaluated. Subsequently, patients were given a placebo for one week followed by naltrexone for one week. In each therapeutic course (placebo or naltrexone) day and night pruritus scores were distinguished by a visual analogue scale (VAS) system and recorded in patients' questionnaires. RESULTS: Both naltrexone and placebo decreased VAS scores significantly. Naltrexone was more effective than placebo in decreasing VAS scores. Both day and night scores of pruritus decreased by half of the value prior to therapy in thirteen patients (38%). Daytime pruritus improved completely in two patients (5.9%), but no improvement in the nighttime values was observed in any patient. Sixteen patients (47%) suffered from naltrexone complications, eleven (32%) of them were related to its withdrawal. Complications were often mild. In the case of withdrawal, the complication was transient (within the first 24-28 h of therapy) and self-limited. We had to cease the drug in two cases (5.9%) because of severe withdrawal symptoms. CONCLUSION: Naltrexone can be used in the treatment of pruritus in cholestatic patients and is a safe drug showing few, mild and self-limited complications.

SBA-15-functionalized 3-oxo-ABNO as recyclable catalyst for aerobic oxidation of alcohols under metal-free conditions.

The nitroxyl radical 3-oxo-9-azabicyclo [3.3.1]nonane-N-oxyl (3-oxo-ABNO) has been prepared using a simple protocol. This organocatalyst is found to be an efficient catalyst for the aerobic oxidation of a wide variety of alcohols under metal-free conditions. In addition, the preparation and characterization of a supported version of 3-oxo-ABNO on ordered mesoporous silica SBA-15 (SABNO) is described for the first time. The catalyst has been characterized using several techniques including simultaneous thermal analysis (STA), transmission electron microscopy (TEM), and nitrogen sorption analysis. This catalyst exhibits catalytic performance comparable to its homogeneous analogue and much superior catalytic activity in comparison with (2,2,6,6-tetramethylpiperidin-1-yl)oxy (TEMPO) for the aerobic oxidation of almost the same range of alcohols under identical reaction conditions. It is also found that SABNO can be conveniently recovered and reused at least 12 times without significant effect on its catalytic efficiency.