Novel Method for Preparation of Bisnorcymerine and Salts Thereof

A method of preparing a salt comprising an acid and a compound of formula 1:

• said method comprising the steps of:
• (i) dissolving one equivalent of said compound of formula 1 in a first volume of a first solvent, to generate a first solution;
• (ii) dissolving a number of equivalents of said acid in a second volume of a second solvent, to generate a second solution;
• (iii) contacting said second solution with said first solution under stirring, to generate a first system comprising a first solid;
• (iv) stirring said first system at a first temperature for a first period of time;
• (v) isolating said first solid from said first system by filtration;
• (vi) washing said first solid with a third volume of a third solvent, to generate a second solid;
• (vii) washing said second solid with a fourth volume of a fourth solvent, to generate a third solid;
• (viii) washing said third solid with a fifth volume of a fifth solvent, to generate a fourth solid;
• and,
• (ix) isolating and removing volatiles from said fourth solid, to generate said salt.