Compound for organic electroluminescent device and organic electroluminescent device

A compound for an organic electroluminescent device represented by the following general formula (I):

• wherein,
• ring a is an aromatic or heterocyclic ring condensed with two adjacent rings and represented by formula (a1) or (a2), ring a′ is an aromatic or heterocyclic ring condensed with three adjacent rings and represented by formula (a1), X is CH or N, and ring b is a heterocyclic ring condensed with two adjacent rings and represented by formula (b1);
• Ar1 is an aromatic heterocyclic group with a valence of m+n,
• L is independently a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted aromatic heterocyclic group and at least one has a condensed ring structure;
• R is independently hydrogen, alkyl group, aralkyl group, alkenyl group, alkynyl group, cyano group, dialkylamino group, diarylamino group, diaralkylamino group, amino group, nitro group, acyl group, alkoxycarbonyl group, carboxyl group, alkoxyl group, alkylsulfonyl group, haloalkyl group, hydroxyl group, amide group, a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted aromatic heterocyclic group;
• m is 1 and n is 1 or 2.