O estudo fitoquímico das raízes de Dahlstedtia glaziovii (Fabaceae) forneceu um novo dibenzoilmetano (glaziovione), juntamente com dezoito compostos conhecidos. Suas estruturas foram determinadas através de métodos espectroscópicos de ressonância magnética nuclear (NMR) 1D e 2D (correlação heteronuclear única quântica, HSQC, e correlação heteronuclear de múltipla ligação, HMBC) e espectrometria de massas de alta resolução (HRMS). A atividade antiproliferativa foi investigada para os extratos, para os dibenzoilmetanos 2'-metóxi-8-(α-α-dimetilalil)-furano-[4",5":3',4']-dibenzoilmetano, 3,4-metilenodioxi-2'-metóxi-8-(α-α-dimetilalil)-furano-[4",5":3',4']-dibenzoilmetano e pongamol, e para as flavonas lanceolatina B, karanjina, pongapina e 3',4'-metilenodioxi-2",2"-dimetilpirano-[5",6":8,7]-flavona. Os dibenzoilmetanos foram mais ativos do que as flavonas. A atividade antimicrobiana foi investigada para os extratos, sendo que estes não se apresentaram ativos.

A phytochemical study of roots of Dahlstedtia glaziovii (Fabaceae) furnished a new dibenzoylmethane (glaziovione), along with eighteen known compounds. Their structures were determined through 1D and 2D nuclear magnetic resonance (NMR) (heteronuclear single quantum coherence, HSQC, and heteronuclear multiple bond correlation, HMBC) and high-resolution mass spectrometry (HRMS) spectral analyses. The antiproliferative activity was investigated for the crude extracts, the dibenzoylmethanes 2'-methoxy-8-(α-α-dimethylallyl)-furano-[4",5":3',4']-dibenzoylmethane, 3,4-methylenedioxy-2'-methoxy-8-(α-α-dimethylallyl)-furano-[4",5":3',4']-dibenzoylmethane and pongamol, and the flavones lanceolatin B, karanjin, pongapin and 3',4'-methylenedioxy-2",2"-dimethylpyrano-[5",6":8,7]-flavone. The dibenzoylmethanes were more active than the flavones.The extracts were evaluated for their antimicrobial effects, but none was shown to be active.

Noctuids are phytophagous lepidopterans with some species causing significant damage to agriculture. The host plants, in turn, have developed defense mechanisms to cope with them, for instance chemical defenses. In this study we review the literature on plant volatiles induced by noctuids, and discuss the methodologies used to induce the production of volatiles that are usually employed in plant defense mechanisms. Future prospects involving this line of research in pest control are also discussed.

The phytochemical investigation of dichloromethane extract from root bark of Lonchocarpus filipes Benth (Leguminosae) afforded four flavonoids including three dibenzoylmethane derivatives rarely found in nature. The structures were established based on their spectral data (¹H and 13C NMR, 2D-NMR) as being: lanceolatin B (1), pongamol (2), (E)-7-O-methylpongamol (3) and (E)-9-O-methylpongamol (4). Compound (4) is described herein for the first time as a natural product. The extracts and the isolated compounds (1), (2) and (3) displayed high toxicity in the brine shrimp lethality assay. Only compound (2) showed antioxidant activity using a DPPH radical scavenging assay. This is the first report on the phytochemical study of Lonchocarpus filipes.

Os conteúdos das glândulas metatorácicas de insetos adultos do percevejo Dichelops melacanthus (Hemiptera: Pentatomidae) foram analisados. Os compostos de defesa foram identificados combinando as técnicas de cromatografia gasosa (CG), cromatografia gasosa acoplada à espectrometria de massas (CG-EM) e por comparação de seus índices de retenção com os de compostos padrões. Tridecano foi o componente majoritário, seguido de quantidades menores e aproximadamente iguais de (E)-4-oxo-2-hexenal e (E)-2-octenal. Também foram identificados (E)-2-hexenal, decano, acetato de (E)-2-hexenila, undecano, (E)-4-oxo-2-octenal, dodecano, acetato de (E)-2-octenila, 1-trideceno, tetradecano e pentadecano.

The contents of metathoracic glands of adults of the stink bug Dichelops melacanthus (Hemiptera: Pentatomidae) were analyzed. Compounds were identified by gas chromatography (GC), coupled GC-mass spectrometry and matching retention indices and mass spectra with those of authentic samples. Tridecane was the major component followed by lesser and approximately equal amounts of (E)-4-oxo-2-hexenal and (E)-2-octenal. Other compounds identified include (E)-2-hexenal, decane, (E)-2-hexenyl acetate, undecane, (E)-4-oxo-2-octenal, dodecane, (E)-2-octenyl acetate, 1-tridecene, tetradecane and pentadecane.