Profile: Synthese AptoChem Inc. specializes in the custom synthesis of stable labeled (D, 13C, 15N) and radiolabeled (14C) reference standards, test articles, pharmaceuticals & their metabolites. We can synthesize a wide variety of small molecules and fine chemicals in milligram to gram scale. We offer custom synthesis services such as stable labeled compounds (D, 13C, 15N), radiolabeled compounds (14C), active pharmaceutical ingredients (API), drug metabolites and pharmaceutical impurities & analogs. Our stable isotopes include abacavir D4, acetaminophen sulfate D4 glucoronide, acetaminophen sulfate D4, acetyl D3-L-carnitine hydrochloride, acetylsalicylic acid-D4, alendronate sodium D6, alfuzosin-D3 hydrochloride, aliskiren-d6, amiodarone-D5 hydrochloride, amlodipine-D9 maleate, amodiaquine-D10 dihydrochloride and amoxapine-D8.