N-(Methyl-d3)-1-propanamine is an intermediate used in the synthesis of 2-Oxo-3-hydroxy-N-methyl-N-propyl D-Lysergamide-d3 (O856883), which is a labeled analogue of 2-Oxo-3-hydroxy-N-methyl-N-propyl D-Lysergamide (O856880), major metabolite of Lysergamide (L487990) used as internal standard;Also, it is the deuterated form of N-Methyl-1-propanamine (M326305), which is a naturally occurring nitrostable secondary amine found in tabacco smoke condensate.