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New C-3 Substituted 1H- and 2H-Indazolephosphonic Acid Regioisomers: Synthesis,...

ABSTRACT: Indazole is known as an important structural motif in medicinal chemistry and, recently, has also gained attention in other areas, such as materials chemistry, with many studies showing different potential applications for their regioisomers. Phosphonates are also a class of compounds with diverse applications, ranging from medicinal to material applications. Here we present the synthesis of 1H- and 2...

Synthesis of novel pyrazolo[3,4-b]quinoline-bisphosphonic acids and an unexpect...

ABSTRACT: Novel pyrazolo[3,4-b]quinoline alpha-ketophosphonic and hydroxymethylenebisphosphonic acid compounds were synthesized using different methodologies, starting from 2-chloro-3-formylquinoline 1. New phosphonic acid compounds were obtained as N-1 derivatives with a side chain with 1 or 3 (n = 1 or 3) methylene groups. All phosphonic acid compounds and their corresponding ester and carboxylic acid precurs...

Asymmetric synthesis of secondary benzylic alcohols via arene chromium tricarbo...

ABSTRACT: The use of O-methyl-N-(alpha-methylbenzyl)hydroxylamine as a novel chiral auxiliary in asymmetric ortho-deprotonation of the (eta(6)-arene) chromium tricarbonyl complexes is described. Upon quenching of the resultant ortho-lithiated complex with an electrophile, 1,2-disubstituted (eta(6)-arene) chromium tricarbonyl complexes were obtained in good yield and excellent levels of diastereoselectivity.

Novel Bisphosphonates Derived from 1H-Indazole, 1H-Pyrazolo[3,4-b]Pyridine, and...

Novel tetraethyl ethylene-1,1-bisphosphonate esters derived from 1H-indazole, 1H-pyrazolo[3,4-b]pyridine, and 1H-pyrazolo[3,4-b]quinoline were synthesized by a Michael addition reaction of tetraethyl ethylidene-1,1-bisphosphonate with the corresponding heterocycle, using conventional heating and microwave-assisted methods. The microwave-assisted method provides shorter reaction times and better yields. The hydr...

New 1-Hydroxy-1,1-bisphosphonates derived from 1H-Pyrazolo[3,4-b]pyridine: Synt...

A number of 1H-pyrazolo[3,4-b]pyridine derivatives, starting from 2-chloro-3-formyl pyridine, was synthesized to obtain new 1-hydroxybisphosphonates, a class of compounds with potential biological interest. Spectroscopic data were used to characterize all compounds and to identify N-1 and N-2 regioisomers, and mono- and bisphosphonates derivatives. X-ray diffractometry studies of compound 7a confirmed the propo...

New 1-Hydroxy-1,1-bisphosphonates derived from 1H-Pyrazolo[3,4-b]pyridine: Synt...

A number of 1H-pyrazolo[3,4-b]pyridine derivatives, starting from 2-chloro-3-formyl pyridine, was synthesized to obtain new 1-hydroxybisphosphonates, a class of compounds with potential biological interest. Spectroscopic data were used to characterize all compounds and to identify N-1 and N-2 regioisomers, and mono- and bisphosphonates derivatives. X-ray diffractometry studies of compound 7a confirmed the propo...

Profile of antimicrobial potential of fifteen Hypericum species from Portugal 

The aim of the present study was the search for the industrial exploitation potential of 15 Hypericum species crops from Portugal. Although Hypericum perforatum is well known worldwide, scarce studies have been published of Hypericum spp. identified in Portugal. Extracts from 15 Hypericum species were screened for its antimicrobial activities against 2 Gram- and 2 Gram+ bacteria, 4 non-tuberculous Mycobacterium...

Impacto na saúde e medidas relacionadas com armas químicas e outros agentes quí...

Neste trabalho é abordado o impacto da utilização de produtos químicos perigosos em acções de terrorismo e são propostas medidas de intervenção que devem ter em conta os cenários previsíveis. Considerando-se primordial a protecção da saúde de grupos alvo, pretende-se sensibilizar as entidades responsáveis para medidas específicas a serem adoptadas por médicos, laboratórios, enfermeiros e brigadas de intervenção...

Novel 1-hydroxy-1,1-bisphosphonates derived from indazole: synthesis and charac...

Bisphosphonates (BPs) are an important class of drugs used in the treatment of abnormal calcium metabolism diseases. The first syntheses of bisphosphonates derived from indazole, substituted at the N-1, N-2 and C-3 positions are reported. The 1-hydroxy-1,1-bisphosphonates were synthesized from the corresponding carboxylic acid or acyl chloride compounds, by two different methods. These BPs have a side chain wit...

New substituted indazole and condensed pyrazole bisphosphonetes