Preparation and biological effects of pure stereoisomeric novel soft anticholinergics.

A series of pure stereoisomeric soft glycopyrrolate analogues 3, 4 and 5 was synthesized using chiral intermediates and by careful separation of the stereoisomers formed during the last quaternization step of the synthesis. The stereochemistry of the products was elucidated using various 1D and 2D NMR techniques. Anticholinergic activity of the new compounds was determined by receptor binding studies and performing tests on isolated organs and by in vivo tests. Receptor binding revealed that in the higher alkyl ester series the (2R, 1'R, 3'R) and the (2R, 1'S, 3'S) isomers were the compounds showing the highest receptor affinity furthermore it demonstrated the confines of the length of the alkyl chain. In vitro isolated organ experiments correlated well with the receptor binding results, and in vivo investigations indicated the soft character of the compounds.

Etiprednol dicloacetate, a new soft glucocorticoid drug candidate. Development of chemistry.

During development of chemistry of the soft drug candidate etiprednol dicloacetate (BNP-166) 1) optimization studies on the three-step chemical synthesis resulted in a process that could be scaled-up to the kg level, 2) the impurity profile was determined, 3) synthetic routes were developed for the preparation of the radiolabeled target compound, and 4) a series of hydroxylated metabolites was prepared.

HPLC separation of related impurities in etiprednol dicloacetate, a novel soft corticosteroid.

Etiprednol dicloacetate (ethyl 17alpha-dichloroacetoxy-11beta-hydroxy-androsta-1,4-diene-3-one-17beta-carboxylate, code-named: BNP-166) has been prepared in a 3-step synthesis from prednisolone as starting material. The primary aim of the present work was to develop HPLC methods for the separation of all the impurities found in experimental pilot plant batches of BNP-166 at concentrations > or = 0.10 area %. Besides BNP-166, a total of 19 compounds, eight of them potential impurities, were involved in the HPLC studies in which several HPLC systems were examined and tested to optimize the separation. Of the parameters influencing chromatographic behaviour column type, the nature and composition of the mobile phase and column temperature were varied, while the pH of the eluent was kept constant at 4.5, a pH value at which stability of the BNP-166 ester bonds was found to be the highest. A comparison of the RRT values obtained allowed some conclusions to be drawn concerning the physico-chemical forces governing separation. The isocratic reversed-phase HPLC system (V02) chosen to be used for various GXP studies on BNP-166 affords baseline separation of nearly all the compounds concerned, and also the quantitation of the drug candidate (BNP-166). By means of this system, it was shown that the target compound prepared by the standardized synthesis method on a pilot plant scale, never contained more than 2-3 impurities with area % values higher than 0.10.

Anti-inflammatory effect and soft properties of etiprednol dicloacetate (BNP-166), a new, anti-asthmatic steroid.

In vitro and in vivo anti-inflammatory properties and soft characteristics of etiprednol dicloacetate (BNP-166) a new steroid, which has been developed for the treatment of asthma, were investigated in this study. The compound effectively decreased cytokine production in lipopolysaccharide stimulated lymphocytes and attenuated lectin-induced proliferation of blood mononuclear cells in tissue culture. In an animal model of allergen sensitized and challenged Brown Norway rats, using topical treatment, etiprednol dicloacetate substantially attenuated the extent of allergen induced bronchoalveolar fluid eosinophilia. At every examined parameter its pharmacological effects were comparable to those of budesonide. By means of in vitro biological and analytical methods the soft character of BNP-166 was also investigated. The anti-inflammatory effect of etiprednol dicloacetate in vitro was shown to be the function of the quantity of serum components, present in the assay. This loss of activity was most likely the result of the fast metabolism of etiprednol dicloacetate, which in the presence of sera could have been demonstrated by LC/MS/MS. Our data indicate that the significant local effect of the compound will very likely be accompanied with a drastically reduced systemic activity indicating an encouraging selectivity of the pharmacological action of etiprednol dicloacetate.

Pharmacological investigation of a new anti-arrhythmic agent, GYKI-23 107.

GYKI-23 107 is a new antiarrhythmic substance with local anaesthetic activity. Its specific pharmacological and cardiovascular effects were studied in vivo and its efficacy was compared with that of lidocaine and mexiletine. GYKI-23 107 was effective against chemically (aconitine and ouabain) induced arrhythmias after both parenteral and oral administration. In aconitine-induced arrhythmia in mice the new compound was more active than either mexiletine or lidocaine after i.p. treatment. In ouabain-induced arrhythmia in dogs, the ED50 of GYKI-23 107 was approximately half that of mexiletine after i.v. injection. GYKI-23 107 and mexiletine produced similar elevation of the fibrillation threshold in anaesthetized cats. After oral pretreatment, GYKI-23 107 showed protective effects against coronary ligation-induced arrhythmia in conscious rats. The circulatory side-effects of GYKI-23 107 in anaesthetized and conscious dogs and cats were milder then those of mexiletine. In the antiarrhythmic dose range there were no adverse cardiovascular actions.