[6R-[6alpha,7beta(Z)]]-3-(acetoxymethyl)-7-[(methoxyimino)[2-(tritylamino)thiazol-4-yl]acetamido]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid (64485-92-3) 's Synthetic route