An efficient and regioselective synthesis of novel 4-aryl-2methyl-N-phenacylimidazoles 5 by a microwave-assisted pseudo-tricomponent reaction between acetamidine hydrochloride (3) and a-bromoacetophenones 2 has been developed. The reduction of the carbonyl group of the ketones 5 offered the corresponding N-(2-hydroxyethyl)imidazoles 6 in good yields. Novel N-substituted imidazoles 5 and 6 were tested for antifungal activity against two clinically important fungi Candida albicans and Cryptococcus neoformans. The results showed that all compounds displayed very low activity against C. albicans. In contrast, compounds 5 and 6 were active against C. neoformans. Among them, ketones 5 showed better activity than alcohols 6, with IC 50 values as low as 15.6 mg/mL for some of them. The difluorinated compound 5 e showed the best activity against C. neoformans, followed by the dichlorinated derivative 5 b. The difluorinated compound 5 e showed the best activity against C. neoformans, followed by the dichlorinated derivative 5 b.

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A selective synthesis of 12R/10H polytypes within the Ba–Ce–Mn–O family can be induced by a Mn precursor.

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A novel series of fully substituted pyrazolo[3,4-b]pyridines 4 has been prepared in a regioselective manner by the microwave-assisted reaction between N-substituted 5-aminopyrazoles 1 and 3-(3-oxo-2-benzofuran-1(3H)-ylidene)pentane-2,4-dione (2). This is the second reported example of a cyclocondensation reaction using substrate 2 as a 1,3-bis-electrophilic reagent. Remarkably, this synthesis offers functionalized products with acetyl and carboxyl groups in one step, in good yields, and with short reaction times. Additionally, the cyclization intermediate 3 was isolated, allowing us to postulate a mechanism for this reaction, which is initiated via isobenzofuranone ring opening of 2 in a Michael-type reaction. The structures of the products and regioselectivity of the reactions were determined on the basis of NMR measurements and X-ray diffraction. For this new reaction using substrate 2, the optimal reaction conditions and its scope were investigated.

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