yǐ xiān dǎn jiǎn
acetylcholine ACh (amine related to vitamin B complex)
乙
yǐ
second of the ten Heavenly Stems 十天干[shi2 tian1 gan1]
酰
xiān
acid radical
胆
dǎn
gall bladder
碱
jiǎn
variant of 鹼|碱[jian3]
