Publications by authors named "I K Liepkaula"

In present study new cyclic fragments of ACTH EHFRWGKPVG--NH2 and KHFRWG--NH2 were investigated in organization of self-stimulation and grooming behaviour in rabbits. Intracerebroventricular injections of EHFRWGPVG--NH2 in doses of 0.1-2.

View Article and Find Full Text PDF

Modified corticotropin fragment - [Lys11 (Gly)]ACTH-(5-14)- and its cyclic analogue - [cyclo (Glu gamma----epsilon Lys (Gly)] ACTH-(5-14)-undecapeptides have been synthesized by classical approach. The cyclic structure has been fixed by amide bond between gamma-COOH group of glutamic acid and alpha-NH2 group of glycine coupled to the epsilon-NH2 group of lysine. Fragment condensation has been achieved by azide or dicyclohexylcarbodiimide methods.

View Article and Find Full Text PDF

A cyclic analogue and the corresponding linear segment of the corticotropin molecule, namely ACTH-(5-14)- and [cyclo (Glu gamma-epsilon Lys)]ACTH-(5-14)-decapeptide, both including the specific and unspecific active centers of the ACTH molecule, have been synthesized and studied. The cyclic structure is fixed by amide bond between the glutamic acid and lysine side chains. Condensation of fragments has been realized by azide or DCC/HOBT methods.

View Article and Find Full Text PDF

Linear and cyclic analogues of the specific active center of the ACTH molecule have been synthesized, viz. [Lis5]ACTH-(5-10)-, [Lys5, cyclo (Gly10----epsilon Lys5)]-ACTH-(5-10)-hexapeptides, [Lys5 (Gly)]ACTH-(5-10)- and [Lys5, Gly11, cyclo (Gly11----epsilon Lys5)]-ACTH-(5-11)-heptapeptides. The cyclic structures are fixed by covalent bond between the COOH-group of the C-terminal glycine and epsilon-amino group of a lysine residue.

View Article and Find Full Text PDF