The present invention relates to a compound which is flexibly amenable to the alteration, without impairing its photosensitivity, of its structural moiety which affects film forming ability and the resulting surface properties, the compound being capable of undergoing surface alteration by irradiation with relatively low energy wavelength, and of forming an organic thin film on a substrate with good reproducibility, and an organic thin film formed body, the compound being represented by formula (1). (In the formula, X represents a heteroatom-containing functional group capable of interacting with a surface of a metal or a metallic oxide, R represents a C1 to C20 alkyl group, a C1 to C20 alkoxy group, an aryl group, or a C1 to C20 alkoxycarbonyl group; n represents an integer of 1 to 30, and m represents an integer of 0 to 5; G1 represents a single bond or a bivalent hydrocarbon radical having carbon atoms of 1 to 3; Ar represents an aromatic group which may have a substituent; G2 represents O, S, or Nr.) ##STR00001##