wherein  (13) A resin comprising:  6  US 9,217,919 B2  5  each ofR$_{0}$ i,  R$_{02 }$and R$_{03 }$independently represents a hydro› gen atom, an alkyl group, a cycloalkyl group, a halogen  atom, a cyano group or an alkoxycarbonyl group, and  R$_{03 }$also may represent an alky lene group and be bonded  toAr$_{1 }$to form a 5-memberedring ora 6-memberedring;  Ar $_{1 }$represents an aromatic ring group;  each of n Y s independently represents a hydrogen atom or  a group capable of leaving by the action of an acid,  provided that at least one of Y s represents a group  capable of leaving by the action of an acid; and  n represents an integer of from 1 to 4, and  at least one repeating unit (A) selected from repeating units  represented by any one of the following general formu› lae (III) to (V);  a repeating unit (B) represented by the following general  formula (I); and  a repeating unit (C) represented by the following general  formula (VI):  each ofR$_{0}$ i,  R$_{02 }$and R$_{03 }$independently represents a hydro› gen atom, an alkyl group, a cycloalkyl group, a halogen  atom, a cyano group or an alkoxycarbonyl group, and  R$_{03 }$also may represent an alky lene group and be bonded  toAr$_{1 }$to form a 5-memberedring ora 6-memberedring;  Ar $_{1 }$represents an aromatic ring group; and  n represents an integer of from 1 to 4.  wherein  (14) A method for producing the compound (P) as set forth in  (1 ).  (15) A method for producing the resin (P) as set forth in (2).  (16) A method for producing the resin as set forth in (13 ).  FIG.  1  is a graph showing an NMR data of the resin (P-1)  synthesized in Synthetic Example 10.  The invention is hereunder described in detail.  As to the expression of a group ( atomic group) in the  specification, the term "group" which does not express  whether it is substituted or unsubstituted includes both one  not having a substituent and one having a substituent. For  example, the term "alkyl group" includes not only an alkyl  group not having a substituent ( an unsubstituted alkyl group)  but an alkyl group having a substituent (a substituted alkyl  group).  <Compound (P)>  The compound (P) contained in the radiation-sensitive  composition is a compound having a partial structure (A)  having an ionic structural site and capable of decomposing  upon irradiation with an actinic ray or radiation to generate an  acid; and a partial structure (B) having at least one phenolic  hydroxyl group, a part or all of hydrogen atoms of the  hydroxyl group or groups each being protected by a group  capable of leaving by the action of an acid, wherein the ionic  structural site of the partial structure (A) is a structure capable  of generating an acid anion in the compound (P) upon irra› diation with an actinic ray or radiation.  Examples of a skeleton of the compound (P) include struc- tures having plural benzene rings and structures having a  cycloalkane structure. More specific examples of the skeleton  include structures disclosed in JP-A-2001-312055, US-A- A represents an ionic structural site capable of decompos- ing upon irradiation with an actinic ray or radiation to  generate an acid anion in a side chain of the resin,  each ofR$_{26}$ , R $_{27 }$and R$_{33 }$independently represents a hydro› gen atom, an alkyl group, a cycloalkyl group, an alkenyl  group, an aryl group or an aralkyl group; and  R$_{25 }$represents an alkyl group, a cycloalkyl group, an alk› enyl group, an aryl group or an aralkyl group;  Ra$_{6 }$ represents a cyano group, a carboxyl group, -CO- OR$_{25 }$or----CO-N(R$_{26}$)(R$_{27}$), and R$_{26 }$and R$_{27 }$may be  bonded to each other to form a ring together with a  nitrogen atom;  each ofR$_{04}$, R$_{05 }$and R$_{07 }$to R$_{09 }$independently represents a  hydrogen atom, an alkyl group, a cycloalkyl group, a  halogen atom, a cyano group or an alkoxycarbonyl  group;  wherein  BRIEF DESCRIPTION OF DRAWINGS  DESCRIPTION OF EMBODIMENTS  Roi Ro2  I  I  *----f-C-Ct-*  I  I  Ro3 Ar1  \  (OH)n  (VI)  (III)  (IV)  Ros  Ro1  I  I  *----f-C-Ct-*  I  I  Ro6 X2  I  A  (V)  Roi Ro2  I  I  *----f-C-Ct-*  I  I  R03 Ar1  \  (0-Y)n  (I)