Structural evaluation of sugar cane bagasse steam pretreated in the presence of CO2 and SO2.

Background: Previous studies on the use of SO2 and CO2 as impregnating agent for sugar cane bagasse steam treatment showed comparative and promising results concerning the cellulose enzymatic hydrolysis and the low formation of the inhibitors furfural and hydroxymethylfurfural for the use of CO2 at 205°C/15 min or SO2 at 190°C/5 min. In the present study sugar cane bagasse materials pretreated as aforementioned were analyzed by scanning and transmission electron microscopy (SEM and TEM), X-Ray Diffraction (XRD) and Infrared (FTIR spectroscopy) aiming a better understanding of the structural and chemical changes undergone by the pretreated materials.

Results: SEM and TEM data showed that the structural modifications undergone by the pretreatment with CO2 were less pronounced in comparison to that using SO2, which can be directly related to the combined severity of each pretreatment.

Thiopurine derivatives containing triazole and steroid: synthesis, antimalarial and antileishmanial activities.

A series of novel 6-thiopurine derivates containing 1,2,3-triazole were synthesized and their in vivo antimalarial activity and in vitro antileishmanial activity were examined. The compounds 10, 11, 12 and 14 presented higher values of inhibition of parasite multiplication than chloroquine. For antileishmanial activity, the compound 14 showed activity against the three species of Leishmania tested.