A reação de enaminonas com o derivado metoximetilênico do ácido de Meldrum forneceu N-adutos e/ou C-adutos das enaminonas, em rendimentos moderados a bons. A regioquímica da reação se revelou dependente do substituinte do nitrogênio da enaminona, e o C-aduto formado é precursor para 2-piridonas. A análise da difração de raios X de dois N-adutos revelou que estes adutos possuem a configuração Z-s-Z.The reaction of acyclic enaminones with methoxymethylene Meldrum's acid afforded N-adduct and/or C-adduct of enaminones in moderate to good yields. The regiochemistry of this reaction depends on the N-amino substituent of the enaminone. The C-adduct is a precursor to 2-pyridones. X-ray analysis of two N-adducts were investigated and the Z-s-Z configuration assigned. Keywords: enaminones, Meldrum's acid, aza-annulation, 2-pyridone IntroductionThe fascinating chemistry of enaminones and their derivatives has attracted the attention of numerous researchers due to their ambiphilic and ambident properties and their potential in the synthesis of heterocyclic compounds.1 In this context, the aza-annulation reaction of cyclic and acyclic enaminones has been extensively used in the preparation of a broad spectrum of nitrogencontaining compounds, 2 mainly in alkaloids 3 and conformationally constrained peptide analogues. 4 Because of these applications several protocols for the synthesis of enaminones have been developed. 5 Among them, the solid support method developed by Braibante and co-workers 6 and its systematic use in the synthesis of pyrazoles and isoxazoles derivatives is noteworthy. 7While the reaction of methoxymethylene Meldrum's acid (1) with cyclic enaminones has been documented (Scheme 1, reactions 1-4), 8 much less study has been carried out with 1 and acyclic enaminones. There is only a single paper describing two examples of reaction of 1 with enaminones 11 and 13a (Scheme 1, reactions 5-6). However, the aza-annulation of derivatives 12 and 14a under pyrolysis conditions (Scheme 1, reaction 7) is not synthetically efficient because mixture of products and poor yields are obtained. In search for a general method of synthesis of derivatives 12 to 14 we undertook a study concerning the reactions of acyclic enaminones and methoxymethylene Meldrum's acid (1). In this paper we report the results of this study with emphasis on synthetic, mechanistic and structural implications. Results and DiscussionEnaminones may act as an ambident nucleophile by reaction at the nitrogen and at the β-carbon. The reactions of enaminones and methoxymethylene Meldrum's acid depend on the N-amino substituent, Scheme 1. C-Adducts are obtained with NR 2 substituent (R = alkyl) and N-adducts with the NH 2 group. However, when we attempted the reaction of enaminone 13a with 1 under the literature condition 8 a low yield of the N-adduct 14a was obtained (36%, instead of the reportedly obtained 60% yield). Additionally, a small quantity of the C-adduct 18a was isolated (3.2% yield, Scheme 2), which was not previously reported. The spectral dat...

Um novo derivado fenólico glucosilado antifúngico, 3,4,5-trimetoxifenil-1-O-β-D-(5-Osiringoila)-apiofuranosil-(1→6)-β-D-glicopiranosideo (1), juntamente com quatro iridóides conhecidos, ácido geniposídico (2), geniposídeo (3), 6α-hidroxigeniposideo (4) e 6β-hidroxigeniposideo (5); duas lignanas, ( (7); e dois ácidos fenólicos, ácidos clorogênico (8) e salicílico (9) e D-manitol (10), foram isolados do extrato etanólico dos galhos de Alibertia sessilis. As estruturas de 1 e dos compostos conhecidos foram determinadas por análise espectroscópica. Todos os compostos isolados foram avaliados quanto à atividade antifúngica frente aos dois fungos fitopatogênicos Cladosporium cladosporioides e C. sphaerospermum por bioautografia direta. (1), together with four known iridoids, geniposidic acid (2), geniposide (3), 6α-hydroxygeniposide (4) and 6β-hydroxygeniposide (5); two lignans, (+)-lyoniresinol-3α-O-β-D-glucopyranoside (6), (-)-lyoniresinol-3α-O-β-D-glucopyranoside (7); and two phenolic acids, chlorogenic (8) and salicylic acids (9) and D-manitol (10), were isolated from the ethanolic extract of the stems of Alibertia sessilis. Structures of 1 and of the known compounds were determined by spectroscopic analysis. All compounds isolated were evaluated for their antifungal activities against two phytopathogenic fungi strains Cladosporium cladosporioides and C. sphaerospermum by direct bioautography. A new antifungal phenolic glycoside, 3,4,5-trimethoxyphenyl-1-O-β-D-(5-O-syringoyl)-apiofuranosyl-(1→6)-β-D-glucopyranoside

Background Glomangioma is a benign tumor of mesenchymal origin, derived from the glomus body. It is responsible for the thermal regulation of the dermis. The occurrence of oncogenic osteomalacia related to glomangioma is rare. Only two cases have been reported thus far. Case presentation A 32-year-old female, Brazilian, presented diffuse pain, during pregnancy, that developed progressively, limiting her mobility. Imaging showed a femoral neck fracture, and rheumatological laboratory examination showed hypophosphatemia. Also, the patient reported episodes of epistaxis during childhood and recurrence along with progressively right nasal obstruction. Endoscopic resection of the tumor was performed, and immunohistochemistry was conclusive for glomangioma. This case report describes the third case in which endonasal endoscopic surgery resulted in a favorable outcome. Conclusion This case of glomangioma-induced oncogenic osteomalacia suggests that surgeons and clinicians should consider sinonasal tumors as a differential diagnosis of osteomalacia, and endonasal endoscopic surgery should be a possible curative resection.