ABSTRACT
Rhipicephalus (Boophilus) microplus is a tick that causes huge economic losses in cattle. The indiscriminate use of acaricides has generated resistance to most compounds present on the market. Carvacrol and salicylic acid have been widely studied for their biological activities and have been evaluated in different strains of Rhipicephalus. In this research the analogues carvacrol and salicylic acid were evaluated in larvae of R. (B.) microplus with data obtained in larval packet test (LPT) and larval immersion test (LIT). A lethal concentration 50 (LC50) was assessed. The most potent compounds were evaluated in the adult ticks since there are no reports of evaluation in the life state of the parasite. From all the tested compounds, the ethyl 2-methoxybenzoate (91.82 ± 1.66%, 0.91 µmol/mL) and ethyl 2,5-dihydroxybenzoate (89.14 ± 1.61%, 2.04 µmol/mL) showed the highest percentage of mortality and the lowest LC50. They were found to be the best candidates for a study in vivo.
ABSTRACT
Chiral diarylmethanols are versatile building blocks for the preparation of biologically active substances, but they are difficult to obtain in enantiopure form. We used Nocardia corallina B-276 for the oxidative kinetic resolution of (+/-)-4-(chlorophenyl)phenylmethanol, 1. Two experimental methods were used: 1) Suspension of cells in a phosphate buffer solution and 2) Cells in the culture media, in a 3-L bioreactor. After 36 hrs using the first method, the ketone/alcohol ratio was 56/44 and the unoxidized alcohol had an enantiomeric ratio of 93/7, predominating the R-alcohol.
