spermidine molecule 3d, molecular structure, ball and stick model, structural chemical formula aliphatic polyamine

spermidine aliphatic polyamine molecule molecular structure chemical formula model c7h19n3 atom nmda receptor agonists secondary amines polyamines chemistry atomic longevity drawing skeletal compound semen youth aging structural icon spermidin synthase science composition illustration carbon oxygen hydrogen organic ageing ball ribosomes bond physics substance nanotechnology line putrescine triamine reaction biochemistry stick