All reagents were of analytical gra

All reagents were of analytical grade. For
methylation reactions, an ethereal solution of diazomethane
(30 ml) was prepared by dissolving 2.14 g of N-methyl- N-ni-troso- p-toluenesulphonamide (Diazald; Aldrich, Steinheim,
Germany) in 10.0 ml of ethanol containing 4.0% potassium
hydroxide.
6)Hydrogenation reactions were carried out under
an atmosphere of hydrogen in the presence of palladium (3.0 or 10.0%) on activated charcoal (Acros Organics, New Jer-sey, U.S.A.) as catalyst.
7)The acetylated chromene was pre-pared by treatment with acetic anhydride (20.0 ml) and pyri-dine (20.0 ml) overnight.
8)Benznidazole, employed as posi-tive control in the assays of trypanocidal activity, was ob-tained from Roche (Rio de Janeiro, Brazil).

ผลลัพธ์ (อังกฤษ) 2:

All reagents were of analytical grade. For
methylation reactions, an ethereal solution of diazomethane
(30 ml) was prepared by dissolving 2.14 g of N-methyl-N-ni-troso - P-toluenesulphonamide (Diazald ; Aldrich, Steinheim,
Germany) in 10.0 ml of ethanol containing 4.0% potassium hydroxide
.
6)
Hydrogenation reactions were carried out under an atmosphere of hydrogen in the presence of palladium (3.0 or 10.0 per cent) on activated charcoal (Acros Organics, New Jer - sey, U.S.A.) As the Catalyst.
7) The acetylated chromene was pre- pared by treatment with acetic anhydride (20.0 ml) and pyri- dine (20.0 ml) overnight.
8) Benznidazole, employed as posi- tive control of assays in the trypanocidal activity, was ob- tained from Roche (Rio de Janeiro, Brazil).