You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 1-[(1R,2R,6R,10S,11R)-2,4-ditert-butyl-9-methyl-2-phenyl-3-oxa-7,8-diaza-6-phospha-2-silatetracyclo[9.4.0.01,5.06,10]pentadeca-4,8,12,14-tetraen-7-yl]ethanone by IUPAC nomenclature, provide its molecular formula.
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C27H35N2O2PSi
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