Asymmetric addition of organozinc compounds to carbonyl groups is one of the most useful methods for the synthesis of alcohols with high enantioselectivity. There is a wide range of chiral catalysts, although their synthesis requires more than one step and not often readily available starting materials. In this work, chiral β-hydroxy oxazolines derived from (+)-camphor and (-)-fenchone were easily synthesized through a one-step method, with good yields. Both ligands were evaluated as catalysts for the stereoselective addition of diethylzinc to aromatic aldehydes. All ligands showed good catalytic activity, leading both to the preparation of the R enantiomer of chiral secondary alcohols. As ligand 2 provided slightly better enantioselectivities, it was used as chiral inductor for the addition of diethylzinc for a larger number of aldehydes, resulting in good to excellent yields (88-98%) and enantiomeric excess up to 96%.

β-Hidroxi-2-oxazolinas quirais foram sintetizadas e avaliadas como catalisadores na adição de dietilzinco a aldeídos. Todas as oxazolinas se mostraram eficientes na obtenção dos produtos de adição. Os melhores excessos enantioméricos (69 a 78%) foram obtidos quando se empregou a β-hidroxi oxazolina quiral derivada da (−)-mentona e do amino álcool 2-amino-2-metilpropan-1-ol.

Chiral β-hydroxy-2-oxazolines were synthesized and evaluated as catalysts for the addition of diethylzinc to aldehydes. All oxazolines proved effective in obtaining the addition products. The best enantiomeric excesses (69-78%) were obtained using the chiral β-hydroxy oxazoline derived from (−)-menthone and the amino alcohol 2-amino-2-methylpropan-1-ol.

O gorgulho-da-casca-do-pinus, Pissodes castaneus (De Geer, 1775) (Coleoptera, Curculionidae) é uma praga florestal que foi detectada no Brasil em 2001 e atualmente se encontra distribuída nos três estados da Região Sul, causando grande preocupação para o setor florestal. Os objetivos deste estudo foram isolar, identificar e avaliar a atividade comportamental dos voláteis produzidos pelos machos de P. castaneus. Nossos resultados indicam que a comunicação entre indivíduos desta espécie é mediada por feromônios, o que foi evidenciado pela atração significativa de fêmeas pelos voláteis produzidos pelos machos. Testes comportamentais realizados com os insetos e sua planta hospedeira, Pinus taeda, indicam que os compostos produzidos pelos machos atuam como feromônios sexuais e que os compostos liberados pela planta hospedeira não aumentam a atividade destes compostos. Os compostos produzidos pelos machos de P. castaneus foram identificados como (1R, 2S)-grandisal e (1R, 2S)-grandisol, em excesso enantiomérico superior a 95%.

The banded pine weevil, Pissodes castaneus (De Geer, 1775) (Coleoptera, Curculionidae) is a forest pest recorded in Brazil since 2001, which is already distributed in the three states of the Southern Region, causing great concern to the forestry sector. Objectives of our study were to isolate, identify, and assess the behavioral activity of male-produced volatiles of P. castaneus. Our results indicate that communication between conspecifics of P. castaneus is mediated by pheromones, as verified by the significant attraction of females to male-produced volatiles. Behavioral tests performed with the insects and the host plant, Pinus taeda, showed that male-produced compounds may act as sex pheromones and that the compounds released by the host plant did not enhance the activity of the male-produced volatiles. The chemical structures of the male specific volatile compounds produced by P. castaneus were determined to be (1R, 2S)-grandisal and (1R, 2S)-grandisol in an enantiomeric excess exceeding 95%.

O estudo fitoquímico das cascas de Guatteria blepharophylla (Mart.) Mart. forneceu 12 compostos, sendo dois sesquiterpenos, óxido de cariofileno (1) e espatulenol (3), uma xantona, liquexantona (2), uma mistura de esteróides, β-sitosterol (4) e estigmasterol (5), e sete alcalóides isoquinolínicos, O-metilmoschatolina (6), lysicamina (7), nornuciferina (8), liriodenina (9), isocoreximina (10), subsessilina (11) e isomoschatolina (12). Suas estruturas foram determinadas através de métodos espectroscópicos. Os compostos 1-6, 11 e 12 são reportados pela primeira vez nesta espécie. Os dados de RMN 13C (ressonância magnética nuclear) para os compostos 11 e 12 são descritos pela primeira vez na literatura. As atividades antiproliferativa em linhagens de células tumorais humanas e antimicrobiana foram investigadas para os compostos majoritários. O composto 9 mostrou significativa atividade contra linhagens de células de mama (MCF-7, Michigan Cancer Foundation-7), superior ao controle positivo doxorrubicina. O composto 12 apresentou atividade antifúngica similar ao controle positivo nistatina contra Candida albicans

Phytochemical study of the bark of Guatteria blepharophylla (Mart.) Mart. afforded twelve compounds, namely two sesquiterpenes, caryophyllene oxide (1) and spathulenol (3), one xanthone, lichexanthone (2), a mixture of steroids, β-sitosterol (4), and stigmasterol (5), and seven isoquinoline alkaloids, O-methylmoschatoline (6), lysicamine (7), nornuciferine (8), liriodenine (9), isocoreximine (10), subsessiline (11), and isomoschatoline (12). Their structures were established on the basis of spectroscopic methods. Compounds 1-6, 11 and 12 were reported for the first time in this species. The 13C NMR (nuclear magnetic resonance) data for the compounds 11 and 12 are described for the first time in the literature. The antiproliferative activity against human tumour cell lines and antimicrobial activities were investigated for the major compounds. Compound 9 showed significant activity against cell lines of breast (MCF-7, Michigan Cancer Foundation-7), superior to the positive control doxorubicin. Compound 12 presented antifungal activity similar to the positive control nystatin against Candida albicans.

Os óleos essenciais de Toona ciliata, Cedrela odorata e C. fissilis foram analisados por CG-EM. Cedrela apresentou em maior percentagem sesquiterpenos formados a partir do precursor pirofosfato de cis- e trans-farnesila. Já Toona mostra uma tendência em produzir principalmente sesquiterpenos derivados do pirofosfato de trans-farnesila. Estes resultados confirmam que a classificação destes dois gêneros em uma mesma tribo, Cedreleae, continua problemática. As respostas em eletroantenogramas médios (EAGs) dos óleos essenciais de T. ciliata e C. odorata, em fêmeas de Hypsipyla grandella, foram significativamente maiores que aquelas obtidas em machos, sugerindo que as fêmeas utilizariam os odores destes óleos para a seleção da planta hospedeira (gêneros de Swietenioidea) e na escolha de locais para oviposição.

The essential oils of Toona ciliata, Cedrela odorata and C. fissilis have been analysed by GC-MS. Cedrela contains the main sesquiterpenes formed from the cis- and trans-farnesyl pyrophosphate. In contrast, Toona tend to produce mainly sesquiterpenes formed from the trans-precursor. These results show that the affiliation of Toona in the tribe Cedreleae together with Cedrela is still rather problematic. Mean electroantennogram responses (EAGs) to the essential oils from T. ciliata and C. odorata, in Hypsipyla grandella females were significantly greater than those obtained for males, suggesting that females would use attractant odours messages from the host-plant (genera of Swietenioideae) as search strategy behaviour for habitat location and oviposition.