IE40824B1 - New antibiotics - Google Patents

Abstract

A process for the preparation of an antibacterially active carboxylic acid compound designated as MM 13902 and salts thereof, which substance MM 13902 is sold carbxylic acid characterised in that its pure di-sodium salt; (i) is highly soluble in water, soluble in methanol and substantially insolubel in chloroform, diethylether and hydro-carbons; (ii) in aqueous solution has an ultra-violet spectrum substnatially as shown in Fig. 1 of the accompanying drawings with absorption maxima at about 305 and 225 mm; (iii) when present at 0.4% w/w in a freshly prepared KBr disc has an infra-red absorption spectrum substantially as shown in Fig. 2, of the accompanying drawings with absorption maxima at inter alia about 3450, 2950, 1750, 1620, 1510, 1400 and 1260cm1; (iv) has an n.m.r. specturm substantially as shown in Fig. 3 of the accompanying drawings when taken in a freshly prepared solution in D2O with inter alia (a) a pair of low fiedl doubelts centred at approximately 2.85GAMMA and 4.00GAMMA with coupling constants of approxiamtely 14 Hz; (b) a doublet centered at approxiamtely 8.55 and (c0 a sharp signlet at approxiamtely 8.00; (v) has the following approxdiamte Rf values ethn run on a cellulose thiin layer chromatogrpahy system; (a) n_butanol/ isopropanol/ water-7:7:6 v/v; Rf=0.72 (b) isopropanol/water-7:3 v/v; Rf=0.85 (c) n-butanol/ethanol/water-7:7:6 v/v; Rf0.81 (d) n-propanol/water-4:1; Rf=0.75; (vi) has an I50 of between 0.001/ug/ml and 0.0001/ug/ml against the beta-lactamase of Escherichia coli B11; (vii) synergises the activity of ampicillin against organisms includign strains of Escherichia coli, Klebnsiella aerogenes, Proteus mirabills, Proteus morganii and Staphylococcus aureus Russell; which process comprises the aerobic grouth of a MM 13902 producing strain of Streptomyces in the presence of assimilable soruces of cabron, nitrogen, sulphur and mineral salts in a solid or semi-solid nutritive medium or in a liquid medium in which the nutrients are dissovled or supsended, at a temperature of 28+/-2degree C for 2 to 3 days and thereafter extracting the antibiotics opresent from the culture medium, either by initial absorption on to and then elution from active characoal or an ion-exchange resin cotnaining tertiary amino grous or quternary ammonium groups or by extracting into a solution of a lipophilic ammonium salt in a water immiscible soluvent at a temperature not exceeding 20degrees C and separatign the MM 13902 therefrom by column chromatograpohy either by using a cellulose or silica-gel column and eluting eith mixtures of water with water-miscible organic solvents or by using columns of ion-exchange resins containing tertiary amino grouups or quarternary ammonium groups and eluting with aqueous solutions of electrolytes buffered to appropriate neutrality. [IN141262A1]