NOVELTY - A nitrogen-containing heterocyclic compound (I), is new.    USE - Nitrogen-containing heterocyclic compound for organic electroluminescent device used for electronic device including organic solar cell, organic photoconductor, organic transistor and single color or white illumination device (all claimed).    ADVANTAGE - The heterocyclic compound provides organic electroluminescent device having high luminous efficiency and durability.    DETAILED DESCRIPTION - A nitrogen-containing heterocyclic compound of formula (I), is new.    m=1-4;    n=1-3;    R1,R2=H, deuterium, tritium, halo, 6-60C aryl, 2-60C heterocyclyl optionally having hetero atom chosen from O, N, S, Si and P, 1-50C alkyl, 2-20C alkenyl, -L2-N(Ar2)(Ar3), 1-30C alkoxy or 6-30C aryl;    Ar1=fluorenyl, 6-60C aryl, 2-20C alkenyl, 2-60C heterocyclyl optionally having O, N, S, Si and P, 1-50C alkyl, -L2-N(Ar2)(Ar3) or 3-60C aromatic ring group;    L1,L2=single bond, 6-60C aryl, fluorenyl, 2-60C divalent heterocyclyl optionally having O, N, S, Si and P, 3-60C aliphatic ring group or 6-60C aromatic ring group;    Ar2,Ar3=6-60C aryl, fluorenyl, 2-60C heterocyclyl optionally having heteroatom chosen from O, N, S, Si and P, 1-50C alkyl, 6-60C aromatic ring group, 3-60C aliphatic ring group or 2-20C alkenyl (all optionally substituted by deuterium, halo, silane, siloxane, boron group, germanium group, cyano, nitro, -L'-N(R')(R"), 1-20C alkylthio, 1-20C alkoxy, 1-20C alkyl, 2-20C alkenyl, 2-20C alkynyl, 6-20C aryl, 6-20C aryl, 2-20C heterocyclyl, 3-20C cycloalkyl, 7-20C aryl, 8-20C alkenyl or aryl);    L'=single bond, 6-60C aryl, fluorenyl, 2-60C hetero atom-containing heterocyclyl, 3-60C aliphatic ring group, 6-60C aromatic ring group or 1-60C divalent aliphatic hydrocarbyl;and    R',R"=6-60C aryl, 2-60C hetero atom-containing heterocyclyl, 1-50C alkyl or 2-20C alkenyl.    INDEPENDENT CLAIMS are included for the following:    (1) organic electroluminescent device containing the nitrogen-containing heterocyclic compound; and    (2) electronic device containing the organic electroluminescent device.    DESCRIPTION OF DRAWING(S) - The drawing shows the schematic view of organic electroluminescent device. (Drawing includes non-English language text)    Substrate (110)    Anode (120)    Light emitting layer (150)    Electron injection layer (170)    Cathode (180)