CCCC>C/CC?tC>HC$C$C$CCCCC>HC>HC$CC>CCCCGsC$C$C$CgCCCC'C$C$CCbCbCAC1CQCbrC19C19C19CC1C1C1CbrCjC19CCbCC1C1CYC19C19C19CyC1C1CC