7-amino-3-methoxymethyl-3-cephem-4-carboxylic acid - useful starting material for pharmaceuticals, is from 7-amino:cephalosporanic acid, methanol and sulphonic acid
摘要
<p>Prepn. of cpd. of formula (I) comprises reacting of 7-amino-cephalosporanic acid of formula (II) or deriv. with a mixt. of MeOH, methanesulphonic acid (III) and trifluoromethanesulphonic acid (IV). Pref. (II) is used in the form of an aromatic sulphonic acid salt, esp. as the p-toluenesulphonic acid dihydrate or its anhydrous analogue. 7-40 equivs. of (III), 0.5-5 equivs. of (IV) and 2-20 equivs. of MeOH are used relative to (II).</p>
