preferred_name: a 1,2-diacylglycerol + glycerol => 2 a 1-acylglycerol
preferred_name_lc: a 1,2-diacylglycerol + glycerol => 2 a 1-acylglycerol
label: a 1,2-diacylglycerol + glycerol => 2 a 1-acylglycerol
label_lc: a 1,2-diacylglycerol + glycerol => 2 a 1-acylglycerol