... > chemical entity > molecular entity > main group molecular entity > p-block molecular entity > pnictogen molecular entity > nitrogen molecular entity > organonitrogen compound > quaternary nitrogen compound > ammonium betaine > meldonium

... > chemical entity > molecular entity > main group molecular entity > p-block molecular entity > carbon group molecular entity > organic molecular entity > heteroorganic entity > organonitrogen compound > quaternary nitrogen compound > ammonium betaine > meldonium

... > chemical entity > molecular entity > main group molecular entity > p-block molecular entity > carbon group molecular entity > organic molecular entity > organic molecule > dipolar compound > zwitterion > onium betaine > ammonium betaine > meldonium

... > chemical entity > molecular entity > polyatomic entity > molecule > organic molecule > dipolar compound > zwitterion > onium betaine > ammonium betaine > meldonium