TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (claimed): The substituted oxepine (I) is prepared by Suzuki coupling reaction. Preferred Process: Alternately, the substituted oxepine (I) is prepared by Buchwald or Ullmann coupling reaction. Preferred Composition: The compound (I) is chosen from 10 substituted oxepine e.g. substituted oxepine of formulae (II)-(VI).Y'=sp2-hybridized carbon atom or X.Preferred Property: The additional compound has band gap of 2.5 eV or more, preferably 3 eV or more, more preferably 3.5 eV or more. FULLL DEFINITIONS:    ring B' condensed with ring A=aryl or heteroaryl, (both optionally substituted with R1);    V'=O, S or C(R4)2, preferably O or S, more preferably O;    X=N or CR1, preferably CR1;    m=0 (monomer), 1 (dimer) or 2 (trimer);    n=0 or 1;    LK=single bond or bifunctional linker substituted with one or more R1, when m is 1, or trifunctional linker substituted with one or more R1 when m is 2;    R1=H, D, F, Cl, Br, I, N(R2)2, CN, NO2, Si(R2)3, B(OR2)2, C(=O)R2, P(=O)(R2)2, S(=O)R2, S(=O)2R2, OSO2R2, or 1-40C linear alkyl, alkoxy or thioalkoxy, 2-40C linear alkenyl or alkynyl, 3-40C branched or cyclic alkyl, alkenyl, alkynyl, alkoxy, alkylalkoxy or thioalkoxy (all optionally substituted by one or more R2), in which one or more non-adjacent CH2- is optionally substituted by R2C=CR2, CC, Si(R2)2, Ge(R2)2, Sn(R2)2, C=O, C=S, C=Se, C=NR2, P(=O)(R2), SO, SO2, NR2, O, S or CONR2 and one or more H are optionally substituted by D, F, Cl, Br, I, CN or NO2, or aryl or heteroaryl having 5-60 aromatic ring atoms (both optionally substituted by R2), aryloxy, arylalkoxy or heteroaryloxy having 5-60 aromatic ring atoms (all optionally substituted by R2), or diarylamino, diheteroarylamino or aryl-heteroaryl amino having 10-40 aromatic ring atoms (all optionally substituted by R2 or cross-linkable group Q), in which two or more adjacent R1 form mono or polycyclic, aliphatic or aromatic or heteroaromatic ring system optionally substituted with one or more R2;    R2=H, D, F, Cl, Br, I, N(R3)2, CN, NO2, Si(R3)3, B(OR3)2, C(=O)R3, P(=O)(R3)2, S(=O)R3, S(=O)2R3, OSO2R3, or 1-40C linear alkyl, alkoxy or thioalkoxy, 2-40C linear alkenyl or alkynyl, 3-40C branched or cyclic alkyl, alkenyl, alkynyl, alkoxy, alkylalkoxy or thioalkoxy (all optionally substituted by R3), in which one or more non-adjacent CH2- is optionally substituted by R3C=CR3, C=C, Si(R3)2, Ge(R3)2, Sn(R3)2, C=O, C=S, C=Se, C=NR3, P(=O)(R3), SO, SO2, NR3, O, S or CONR3 and one or more H is optionally substituted by D, F, Cl, Br, I, CN or NO2, or aryl or heteroaryl having 5-60 aromatic ring atoms (both optionally substituted by R3), aryloxy, arylalkoxy or heteroaryloxy having 5-60 aromatic ring atoms (all optionally substituted by R3), or diarylamino, diheteroarylamino or aryl-heteroaryl amino having 10-40 aromatic ring atoms (all optionally substituted by R3), in which two or more adjacent R2 form mono or polycyclic, aliphatic or aromatic or heteroaromatic ring system;    R3=H, D, F or 1-40C aliphatic, aromatic and/or heteroaromatic hydrocarbyl, in which one or several H is optionally substituted by F, and two or more R3 form mono or polycyclic, aliphatic, aromatic or heteroaromatic ring system;and    R4=R1, in which two R4 do not form ring closure.    N.B: R4 is defined, but does not appear in any other structure. (i) The ring A beside the ring B' contains 2 or more aromatic or heteroaromatic ring or ring system which are fused directly to the 7-membered ring A of formula (I), further fused to ring A or ring system optionally substituted with one or more R1; (ii) When m is 0, at least one R1 is not H; (iii) When n is 0, m is 0; and (iv) When n is 1, m is 1 or 2.    ACTIVITY - Dermatological; Antiseborrheic. No biological data given.    MECHANISM OF ACTION - None given.