A monoazo compound of the formula, ##STR1## wherein D is a heterocyclic or carbocyclic compound residue such as benzothiazolyl and phenyl, X is hydrogen, alkyl, alkoxy, halogeno, acylamino or the like, Y is hydrogen, halogeno, alkyl, alkoxy and the like, R.sub.1 is alkyl, R.sub.2 is C.sub.2 -C.sub.4 alkylene, B is a bridging group such as ##STR2## --O--, --S--, C.sub.1 -C.sub.6 alkylene and the like, and W.sub.1, W.sub.2, W.sub.3, Z.sub.1, Z.sub.2 and Z.sub.3 are independently hydrogen, alkyl, halogeno or the like, which is useful for dyeing hydrophobic fiber materials to give dyed or printed product of a deep color excellent in fastness properties, particularly those such as washing fastness, even after various finishing treatments of the product.