Resist composition, method for forming resist pattern, and polyphenol compound used therein

A resin having a structure represented by the following general formula (Z):

• wherein each X is independently an oxygen atom, or a sulfur atom;
• R1 is a 2n-valent group of 1 to 30 carbon atoms;
• R2 and R3 are each independently a halogen atom, a linear, branched, or cyclic alkyl group of 1 to 10 carbon atoms, an aryl group of 6 to 10 carbon atoms, an alkenyl group of 2 to 10 carbon atoms, an alkoxy group of 1 to 30 carbon atoms, a thiol group, or a hydroxy group;
• each Y is independently a single bond or a linear or branched alkylene group of 1 to 20 carbon atoms;
• each m2 is independently an integer of 0 to 6, provided that at least one m2 is an integer of 1 to 6;
• each p is 1;
• and n is an integer of 1 to 4;
• provided that R1 is a group comprising an iodine atom, and at least one R2 and/or at least one R3 is one or more selected from a hydroxy group and a thiol group.