In this work, a racemization method of (S)-1-phenylethanol by niobium salts was developed. Among the salts available, the niobium phosphate hydrate (NbOPO4.nH2O) reduced the enantiomeric excess (ee) of the chiral alcohol from 95 to 0% after 24 h at 60 ºC in toluene. This new racemization agent was combined with a lipase (CALB) in order to achieve a chemoenzymatic dynamic kinetic resolution (DKR). Experiments demonstrated that the DKR process is feasible and the corresponding (R)-1-phenylethyl acetate was obtained with 92% conversion and 85% ee.

Intrigued by the recent discovery of caramboxin by Brazilian researchers, we present the results from our studies toward the racemic synthesis of caramboxin analogs through the ortho-carboxylation of 3,5-dimethoxy benzyl derivatives. Three different approaches were tested, and the route involving a Vilsmeier-Haack formylation followed by a Lindgren oxidation provide a potential intermediate for the synthesis of several caramboxin analogs.

RESUMO O objetivo foi avaliar a eficiência dos modelos fenotípicos de competição, via análise espacial, na avaliação genética de testes de progênies de Pinus taeda L. Para isso foram utilizadas quatro covariáveis de competição para ajuste dos valores fenotípicos em um teste de progênies de P. taeda plantado em quatro diferentes locais no estado de Santa Catarina. O teste foi implantado em delineamento de blocos casualizados, com sete repetições, parcelas lineares de seis plantas e espaçamento de 2,5 m x 2,0 m. O teste instalado nos locais A, B e D possuem 63 famílias e no local C 53 famílias. Aos nove anos de idade foi efetuada a mensuração da variável diâmetro à altura do peito de todos os indivíduos. A presença ou não da competição foi baseada nos coeficientes de autocorrelação residual, que teve sua significância testada pelo teste de Durbin-Watson. No geral, o uso de covariáveis corrigiu o efeito da competição e as variâncias entre e dentro de parcela e o coeficiente de variação residual foram reduzidos. A análise espacial foi apropriada para validar a eficiência das covariáveis. A classificação pelo efeito genético dos indivíduos no teste de progênies foi extremamente alterada para o conjunto de dados com e sem o uso de covariáveis para os locais A e D, assim como a interação genótipo x ambiente. O uso dessas duas ferramentas é de suma importância na análise de dados em testes de progênies de P. taeda, pois os efeitos de competição podem conduzir a erros na seleção de indivíduos e na definição de zonas de melhoramento.

ABSTRACT The objective of this study was to evaluate the efficiency of the phenotypic models of competition, through spatial analysis in the genetic evaluation of Pinus taeda L progenies. For this, four competition covariates were used to adjust the phenotypic values in a P. taeda progeny test installed in four different locations in the state of Santa Catarina. The test was implemented in randomized block design, with seven repetitions, linear plots containing six plants per plot in 2.5 m x 2.0 m spacing. The test installed in sites A, B, and D present 63 families and site C 53 families. At nine years old, the diameter at the breast height was measured for all individuals. The presence or absence of competition was based on the residual autocorrelation coefficients, which had its significance tested by the Durbin-Watson test. In general, the use of covariates corrected the competition effect. The variances among and within plots, as well as the residual variation coefficient, were reduced. The classification by the genetic effect of the individuals in the progeny test was extremely altered for this data set with and without the use of covariates for sites A and D, as well as the genotype x environment interaction. The use of these two tools is of great importance in the analysis of data in P. taeda progeny tests, since the effects of competition can lead to mistakes in the selection of individuals and in the definition of improvement zones.