Main Reaction: GTP >> D-erythro-dihydroneopterin triphosphate

Reference: PubMed ID: 4004850
Authors: Milstien S, Kaufman S
Title: Biosynthesis of tetrahydrobiopterin: conversion of dihydroneopterin triphosphate to tetrahydropterin intermediates.
Published: 1985 May 16

GTP --> D-erythro-dihydroneopterin triphosphate