Es werden die Verbindungen und die Synthese von [F-18] markierter L-Glutaminsäure, [F-18] markiertem L-Glutamat, ihren Derivaten gemäß Formel (I) und ihre Verwendungen beschrieben.Amide compounds (I) are new. Amide compounds of formula (I) are new. A : OH, 1-5C-alkoxy, hydroxy 1-5C-alkoxy, O-1-5C-alkyl-(O-1-4C-alkyl) n-O-1-4C-alkyl, N(1-5C-alkyl) 2, NH 2, N(H)-L, O-L or O-Z G : OH, O-Z, O-1-5C-alkyl, O-2-5C-alkenyl, O-1-5C-alkyl-(O-1-4C-alkyl) nO-1-4C-alkyl, O-2-5C-alkynyl, or triphenylmethoxy R 1>, R 2> : H, 1> 8>F-2-5C-alkoxy, 1> 8>F-1-5C-alkyl, 1> 8>F-2-5C-alkenyl, 1> 8>F-2-5C-alkynyl, OH, 1-5C-alkyl or 1-5C-alkoxy L : 1-5C-alkyl, 2-5C-alkenyl, 1-5C-alkyl-(O-1-4C-alkyl) n-O-1-4C-alkyl or 2-5C-alkynyl Z : a metal cation equivalent and n : 0-3. Provided that one of the substituents R 1>or R 2>contains 1> 8>F isotope and the other substitution is free of 1> 8>F isotope and R 1>is not H. Independent claims are included for: (1) a carbonyl compound of formula (II) (2) the preparation of (I) (3) the preparation of (II) comprising reacting a carbonyl compound of formula (III) with F-18 fluoride (4) the carbonyl compound (III) (5) use of a pyrrolidine compound of formula (IV) for the preparation of (I) or (II) (6) a kit comprising (III) or (IV) and (7) a pharmaceutical composition comprising (I)-(IV) and a suitable carrier. A 1> : OH, 1-5C-alkoxy, hydroxy 1-5C-alkoxy, O-1-5C-alkyl-(O-1-4C-alkyl) n-O-1-4C-alkyl, N(1-5C-alkyl) 2, NH 2, N(H)-L 1>, O-L 1> G 1> : OH, O-Z 1>, O-1-5C-alkyl, O-2-5C-alkenyl, O-1-5C-alkyl-(O-1-4C-alkyl) nO-1-4C-alkyl, O-2-5C-alkynyl, or triphenylmethoxy Q : N(H)-tert-butoxycarbonyl, N(H)-benzyloxycarbonyl, -N=C(X 1>)(X 2>) (all preferred), N(H)-allyloxycarbonyl, N(H)-ethoxycarbonyl, N(H)-methoxycarbonyl, N(H)-propoxycarbonyl, N(H)-2,2,2-trichloroethoxycarbonyl, N(H)-1,1-dimethylpropinyl, N(H)-1-methyl-1-phenyl-ethoxycarbonyl, N(H)-1-methyl-1-(4-biphenylyl)-ethoxycarbonyl, N(H)-cyclobutylcarbonyl, N(H)-cyclobutylcarbonyl, N(H)-1-methylcyclobutylcar
