(2R,3S,4S)-1-(2-Phenylhydrazono)-pentane-2,3,4-triacetate-d3 is an intermediate used in the synthesis of Biopterin-d3 (B389022) which is labeled Biopterin, an pteridine widely distributed in nature; naturally occurring as the L-erythro-form. Considered as a growth factor for some insects. Fluoresces with a blue color in alkaline solution.