Introduction Organic derivatives of ammonia. Many are biologically active. CH2一CH-COOH OH :NH2 HO CH2 HO CH-CH2-N CH2 CH3 HO HN HO H dopamine epinephrine L-tryptophan a neurotransmitter an adrenal hormone an amino acid 0 CH2OH CH2CH2NH2 HO CH2OH OH H一) H:C > piperazine nicotinic acid pyridoxine histamine kills intestinal worms niacin,a vitamin vitamin B6 dilates blood vessels Copyright 2005 Pearson Prentice Hall,Inc.Chapter 19 2 Introduction • Organic derivatives of ammonia. • Many are biologically active. =>