[2R-(2α,3Z,5α)]-3-(2-Hydroxyethylidene)-7-oxo-4-oxa-1-azabicyclo[3.2.0]heptane-2-carboxylic Acid, compd. with 2,4,4-Trimethyl-2-pentanamine (1:1); 2,4,4-Trimethyl-2-pentanamine (2R,3Z,5R)-3-(2-Hydroxyethylidene)-7-oxo-4-oxa-1-azabicyclo[3.2.0]heptane-2-carboxylate; 2,4,4-Trimethyl-2-pentanamine [2R-(2α,3Z,5α)]-3-(2-Hydroxyethylidene)-7-oxo-4-oxa-1-azabicyclo[3.2.0]heptane-2-carboxylate