胞嘧啶

胞嘧啶	bāo mì dìng	cytosine nucleotide (C, pairs with guanine G 鸟嘌呤 in DNA and RNA)
胞	bāo	placenta / womb / born of the same parents
嘧	mì	(phonetic) as in pyrimidine
嘧啶	mì dìng	pyrimidine C4H4N2
啶	dìng	idine (chemistry)