Synthesis of uracil derivatives by oxidation of Fischer tungsten–carbene uracil complexes

A study on the oxidation of Fischer tungsten-carbene uracil complexes has been carried out. Several commonly used oxidants gave results strongly influenced by the presence of substituent on nitrogen atoms. In particular, usual oxidants failed in the oxidation of 3-alkyl uracil carbene complexes. Finally, we showed that t-butyl hydroperoxide is able to oxidize successfully also 3-alkyl uracil carbene complexes and can be used as a good alternative to the other methods. (c) 2006 Elsevier B.V. All rights reserved

Preparation of organometallic uracil-analogue Fischer carbenecomplexes: Comparative study of conventional heatingvs microwave irradiation

Mono and disubstituted ureas react with alkynyl Fischer carbene complexes to give mono and di N,N-substituted organometallic uracil analogues. An optimization of the process using different starting metal carbene complexes and variously substituted ureas under conventional heating (with and without solvent) and microwave irradiation techniques is reported. The synthesis of the metal–carbene analog of the commercially available dimethyl uracil is reported

On the influence of unsaturation on the macrolactonization of hydroxy fatty acids

A simple and efficient regiocontrol of the macrolactonization reaction can be obtained by controlling the reaction temperature. In fact, while energetic factors favour the formation of the smaller ring, entropic factors drive the cyclization toward the formation of the larger ring. There are two different physico-chemical factors which contribute to the entropic term: the higher number of conformers of the larger ring and vibrational contributions arising from low frequency modes. Work aimed to better elucidate the relative weight of these two factors is in progress

Double-blind, randomized controlled trial of interleukin-2 treatment of chronic hepatitis B.

Pilot studies have demonstrated that recombinant interleukin 2 (rIL-2) has an indirect antiviral activity against hepatitis B virus, but the minimal dose of rIL-2 for induction of this effect was not defined. The aim of the study was to ascertain the most efficient dose of rIL-2 for induction of the loss of detectable serum HBV-DNA or a 50% or greater decrease in its level. Thirty-one patients with chronic hepatitis B, hepatitis B e antigen and serum HBV-DNA positive were enrolled in this double-blind randomized controlled trial. Patients were divided: Group I (n = 8) placebo; Group II (n = 7) treated with 0.9 MU of rIL-2 subcutaneously administered daily for 8 weeks; Group III (n = 8) treated with 1.8 MU of rIL-2 under the same schedule; Group IV (n = 8) which received 3.6 MU of rIL-2 under the same conditions. At the end of treatment 25% of the patients in the placebo group, and 13% and 25% in rIL-2 groups III and IV, respectively, had a decrease in HBV-DNA higher than 50% of the basal value. None of the patients lost serum HBV-DNA. Only three patients (one from group II and two from group IV) normalized the ALT levels. Overall, during treatment, ALT levels decreased in the treated groups. This decrease occurred simultaneously with an increase in serum HBV-DNA concentration. Since the response rate in the treated groups was similar to that of the placebo group, rIL-2 is not useful as monotherapy for the treatment of chronic hepatitis B at the doses and schedules used in this study