Roussel Uclaf

About: Roussel Uclaf is a based out in . It is known for research contribution in the topics: Alkyl & Alkoxy group. The organization has 1888 authors who have published 2338 publications receiving 36508 citations.

New ether oxime derivatives of erythromycin A. A structure-activity relationship study.

Abstract: The discovery of roxithromycin is the result of a rational and scientific process, based on the fact that at least one reason for erythromycin A's resorption variability after oral administration was its instability in the gastric juice. This instability is due to the reactivity of the ketone in position 9 in acidic medium and one chemical approach was to mask it by an oxime function. Both stereoisomers of this oxime were isolated. Direct O-alkylation of this oxime allowed access to various ether oxime derivatives and of the latter the E stereoisomers were more interesting than the Z ones. The choice of the nature of the oxime substitution was made according to the lipophilic or hydrophilic character of the aliphatic ether chain and these alterations were mainly carried out by introducing heteroatoms into this chain. These different derivatives were classified in 5 groups according to the chemical nature of the chain: Aliphatic, aromatic and nitrogen-, oxygen- and sulfur-containing chains. Two classes, those containing a nitrogen or an oxygen in the ether side chains, showed differential in vitro/in vivo antibiotic activities, with improved bioavailability. Some preliminary pharmacokinetic data confirmed this improvement and led to the selection of five candidates, from which roxithromycin emerged as the best compound.

Recent Advances in the Total Synthesis of Steroids

Abstract: In the total synthesis of steroids on the industrial scale, three factors are important: stereoselectivity of the reactions used, resolution of racemic intermediates at the earliest possible stage, and convergence of the synthesis Theoretical advances and wider practical experience in the chemistry of polycyclic compounds have recently led to the development of the first syntheses which are suitable for the industrial production of steroid hormones

Treatment with neutralizing antibodies specific for IL-1beta prevents cyclophosphamide-induced diabetes in nonobese diabetic mice.

Abstract: Interleukin-1 (IL-1) has been shown to be involved in the pathogenesis of IDDM, but it is not clear which form, IL-1alpha or IL-1beta, is predominantly implicated. In this study, we have evaluated the contribution of IL-1beta by treating diabetes-prone nonobese diabetic (NOD) mice with specific neutralizing antibodies. First, we assessed the neutralizing potential of these antibodies in C57BL/6 mice under acute septic shock by measuring IL-1beta in sera 4 h after lipopolysaccharide injection. One milligram and 0.1 mg of anti-IL-1beta antibodies (Abs) were capable of neutralizing the IL-1beta produced, and the effect persisted for at least 5 days. Second, we evaluated the role of IL-1beta in the cyclophosphamide (CY)-accelerated model of diabetes. Nondiabetic male NOD mice were injected with 200 mg/kg CY and treated twice weekly with anti-IL-1beta Ab. The incidence of diabetes reached 76 and 100% in the control groups treated with 0.25 and 0.1 mg rabbit IgG, respectively. In contrast, only 34% of mice treated with 0.25 mg of anti-IL-1beta Ab became diabetic. In the group treated with 0.1 mg of anti-IL-1beta Ab, 89% of the mice became diabetic in the same period of time, demonstrating that the protective effect was dose dependent. Our results show that IL-1beta is a critical effector molecule in this model of IDDM and that its specific inhibition could be an attractive target for therapeutic intervention.

3-Acetoxymethyl-7-(iminoacetamido)-cephalosporanic acid derivatives

Abstract: Compounds of the formula ##STR1## wherein R is selected from the group consisting of hydrogen and groups easily removable by acid hydrolysis or hydrogenolysis, R' is selected from the group consisting of hydrogen, alkyl of 1 to 4 carbon atoms, alkenyl and alkynyl of 2 to 4 carbon atoms and groups easily removable by acid hydrolysis or hydrogenolysis, A is selected from the group consisting of hydrogen, alkali metal and equivalents of an alkaline earth metal or magnesium and an organic amine base with the proviso that when R' is a group easily removable by acid hydrolysis or hydrogenolysis, R is also and when R' is hydrogen, R also is hydrogen and the wavy line means the OR' group may be in either one of the two possible syn or anti positions having antibiotic activity and process for their preparation.