LUTEINIZING AND FOLLICLE-STIMULATING HORMONES RELEASING FACTOR ANALOGS WITH A HIGH GONADOTROPIC ACTIVITY AND A PROCESS FOR THE PREPARATION THEREOF

摘要

The present invention relates to new, biologically active nonapeptides of the general formula (I) 1 2 3 4 5 6 7 9 pGlu-His-Trp-Ser-Tyr-D-Tle-Leu- IMG -Pro-NH-Et (I) wherein X represents a hydrogen atom or a protective group, preferably a p-toluenesulfonyl (tosyl) radical. These new substances are synthetic analogs of the luteinizing and follicle-stimulating hormones releasing factor and have high gonadotropic activity. The substances are expected to find use in human and veterinary medicine, especially for the control of the estral cycle, for the treatment of estral disturbances or as a nonsteroidal contraceptive. The nonapeptide compounds of the formula (I) can be prepared by processes which comprise reactions of combining the respective amino acid or lower peptide radicals with the use of preparative methods of the peptide chemistry. Preferable original methods for the elimination of the protective tosyl group in the position 8 and for the isolation and purification of the successive products are described.