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system
What is the molecular formula of the molecule 18-hydroxy-11,17-dioxa-3-thia-5-azapentacyclo[10.7.1.02,10.04,9.016,20]icosa-1(20),2(10),4(9),5,7,12,15,18-octaen-14-one ?
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C16H7NO4S
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