Organic electroluminescent compound and organic electroluminescent device comprising the same

An organic electroluminescent compound represented by the following formula 1:

• wherein
• X and X1, each independently, represent O or S;
• HAr represents a substituted or unsubstituted (3- to 30-membered)heteroaryl;
• L1 represents a single bond, a substituted or unsubstituted (C6-C30)arylene, or a substituted or unsubstituted (3- to 30-membered)heteroaryene;
• R1 represents a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C6-C30)aryl, a substituted or unsubstituted (3- to 30-membered)heteroaryl, or a substituted or unsubstituted (C3-C30)cycloalkyl;
• R2 and R3, each independently, represent hydrogen, deuterium, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C6-C30)aryl, a substituted or unsubstituted (3- to 30-membered)heteroaryl, or a substituted or unsubstituted (C3-C30)cycloalkyl, or may be linked to adjacent one(s) of R2 and R3 to form a ring(s);
• and
• n and m represent an integer of 1 to 3;
• in which if n and m, each independently, are an integer of 2 or more, each of R2 or each of R3 may be the same or different.