NOVELTY - Organic electroluminescent compounds are new.    USE - In an organic electroluminescent device, particularly as an organic electroluminescent display which is useful in an organic solar cell (claimed). Also used as green electroluminescent material.    ADVANTAGE - The electroluminescent compounds provide excellent luminous efficiency with very good device life as compared to conventional dopant material, and provide organic electroluminescent devices with high efficiency and long life which employ the organic electroluminescent compounds. Since organic electroluminescent compounds exhibit high luminous efficiency and excellent color purity and life property of material. The organic electroluminescent compounds are advantageous to manufacture organic light emitting diodes (OLED's) having very good operation life.    DETAILED DESCRIPTION - Organic electroluminescent compounds of formula (I) are new.    R1 and R2=T1 or a group of formulae (ia) to (ic);    T1=H, halo, (1-60C)alkyl, (6-60C)aryl, (3-60C)heteroaryl, 5- or 6-membered heterocycloalkyl (containing at least one heteroatom(s) selected from N, O, S or Si), (3-60C)cycloalkyl, tri(1-60C)alkylsilyl, di(1-60C)alkyl(6-60C)arylsilyl, tri(6-60C)arylsilyl, adamantyl, (7-60C)bicycloalkyl, (2-60C)alkenyl, (2-60C)alkynyl, (1-60C)alkoxy, (1-60C)alkylthio, cyano, (1-60C)alkylamino, (6-60C)arylamino, (6-60C)ar(1-60C)alkyl, (6-60C)aryloxy, (6-60C)arylthio, (1-60C)alkoxycarbonyl, carboxyl, nitro or hydroxyl (where the alkyl, (hetero)aryl, (hetero)cycloalkyl, trialkylsilyl, dialkylarylsilyl, triarylsilyl, adamantyl, bicycloalkyl, alkenyl, alkynyl, alkylamino or arylamino all optionally further substituted by at least one substituent(s) selected from halo, (1-60C)alkyl optionally with halo substituent(s), (6-60C)aryl, (3-60C)heteroaryl optionally with (6-60C)aryl substituent(s), 5-or 6-membered heterocycloalkyl (containing at least one heteroatom(s) selected from N, O, S or Si), (3-60C)cycloalkyl, tri(1-60C)alkylsilyl, di(1-60C)alkyl(6-60C)arylsilyl, tri(6-60C)arylsilyl, adamantyl, (7-60C)bicycloalkyl, (2-60C)alkenyl, (2-60C)alkynyl, (1-60C)alkoxy, (1-60C)alkylthio, cyano, (1-60C)alkylamino, (6-60C)arylamino, (6-60C)ar(1-60C)alkyl, (6-60C)aryloxy, (6-60C)arylthio, (1-60C)alkoxycarbonyl, carboxyl, nitro or hydroxyl);    R3-R15=T1;or    R3 to R15 optionally linked to an adjacent substituent via (3-60C)alkylene or (3-60C)alkenylene optionally with a fused ring=an alicyclic ring, or monocyclic or polycyclic aromatic ring;    X and Y1=bond, -(CR21R22)n-, -N(R23)-, -S-, -O-, -Si(R24)(R25)-, -P(R26)-, -C(=O)-, -B(R27)-, -In(R28)-, -Se-, -Ge(R29)(R30)-, -Sn(R31)(R32)-, -Ga(R33)- or -(R34)C=C(R35)-;    R21 to R35=T1;or    R21+R22, R24+R25, R29+R30, R31+R32, or R34+R35 optionally linked via (3-60C)alkylene or (3-60C)alkenylene optionally with a fused ring=an alicyclic ring, or a monocyclic or polycyclic aromatic ring;    ring A'and ring B'=saturated 5- or 6-membered heterocyclic amino group (which optionally further contain at least one heteroatom(s) selected from NR36, O or S), or a group of formula (id) or (ie);    R36=H, halo, (1-60C)alkyl, (6-60C)aryl, (3-60C)heteroaryl, (3-60C)cycloalkyl, adamantyl, (7-60C)bicycloalkyl or (6-60C)ar(1-60C)alkyl;    R41 to R48=T1;or    R41 to R48 = optionally linked to an adjacent substituent via (3-60C)alkylene or (3-60C)alkenylene optionally with a fused ring to form an alicyclic ring, or a monocyclic or polycyclic aromatic ring;    Z1=bond, -(CR51R52)m-, -N(R53)-, -S-, -O-, -Si(R54)(R55)-, -P(R56)-, -C(=O)-, -B(R57)-, -In(R58)-, -Se-, -Ge(R59)(R60)-, -Sn(R61)(R62)-, -Ga(R63)- or -(R64)C=C(R65)-;    R51 to R65=T1;or    R51+R52, R54+R55, R59+R60, R61+R62, or R64+R65 optionally linked via (3-60C)alkylene or (3-60C)alkenylene optionally with a fused ring=an alicyclic ring, or a monocyclic or polycyclic aromatic ring;    m and n=1-4;    a and b=0-4;    (a+b)=1-4.    An INDEPENDENT CLAIM is included for an organic electroluminescent device which is comprised of a first electrode; a second electrode; and at least one organic layer(s) interposed between the electrodes, where the organic layer comprises the organic electroluminescent compound (I) and at least one host(s) selected from compounds of formula (Ar1)c-L11-(Ar2)d (VI) or (Ar3)e-L12-(Ar4)f (VII).    L11=(6-60C)arylene or (C4-C60)heteroarylene;    L12=anthracenylene;    Ar1 to Ar4=H, (1-60C)alkyl, (1-60C)alkoxy, halo, (4-60C)heteroaryl, (5-60C)cycloalkyl or (6-60C)aryl (where the cycloalkyl or (hetero)aryl optionally further substituted by at least one of (6-60C)aryl or (4-60C)heteroaryl (optionally with at least one substituent(s) selected from (1-60C)alkyl optionally with halo, (1-60C)alkoxy, (3-60C)cycloalkyl, halo, cyano, tri(1-60C)alkylsilyl, di(1-60C)alkyl(6-60C)arylsilyl or tri(6-60C)arylsilyl), (1-60C)alkyl optionally with halo, (1-60C)alkoxy, (3-60C)cycloalkyl, halo, cyano, tri(1-60C)alkylsilyl, di(1-60C)alkyl(6-60C)arylsilyl or tri(6-60C)arylsilyl);    c, d, e and f=0-4.