The Salk Institute for Biological Studies

Carl A Hoeger

Jean E Rivier

John S Porter

Paula G Theobald

Catherine L Rivier

Wylie W Vale, Jr

Jean E F Rivier

Wylie Walker Vale, Jr

Guangcheng Jiang

Peptides which include unnatural amino acids and which either promote or inhibit the secretion of gonadotropins by the pituitary gland and inhibit the release of steroids by the gonads. Administration of an effective amount of such peptides that are GnRH antagonists prevents ovulation of female mammalian eggs and/or the release of steroids by the gonads and may be used to treat steroid-dependent tumors. The agonists can be used for control of reproduction processes, to treat precocious puberty, endometriosis, and the like. The peptides are analogs of the decapeptide GnRH wherein there is at least one residue of an unnatural amino acid in the 3-, 5-, 6- and/or 8-positions. Unnatural amino acids having the following formula are incorporated in a preferred group of synthesized peptides:

Peptides intermediates for making GnRH antagonists

Analogs of SRIF which are selective for SSTR1 in contrast to the other cloned SRIF receptors. These analogs are useful in determining the tissue and cellular expression of the receptor SSTR1 and its biological role in the endocrine, exocrine and nervous system, as well as in regulating tumor growth. SRIF analog peptides, such as des-AA.sup.1,2,5 �D-Trp.sup.8, IAmp.sup.9 !-SRIF inhibit the binding of �.sup.125 I-Tyr.sup.11 !SRIF to the cloned human receptor SSTR1 but do not bind to mouse SSTR2 and SSTR3, human SSTR4 or rat SSTR5. By incorporating an iodinated tyrosine in position-2 in these selective SRIF analogs, a labelled compound useful in drug-screening methods is provided.

Receptor-selective somatostatin analogs

Peptides which include unnatural amino acids and which either promote or inhibit the secretion of gonadotropins by the pituitary gland and inhibit the release of steroids by the gonads. Administration of an effective amount of such peptides that are GnRH antagonists prevents ovulation of female mammalian eggs and/or the release of steroids by the gonads and may be used to treat steroid-dependent tumors. The agonists can be used for control of reproduction processes, to treat precocious puberty, endometriosis, and the like. The peptides are analogs of the decapeptide GnRH wherein there is at least one residue of an unnatural amino acid in the 3-, 5-, 6- and/or 8-positions. Unnatural amino acids having the following formula are incorporated in a preferred group of synthesized peptides: ##STR1## Methods for synthesizing such peptides having the triazole side chains are disclosed wherein one side chain modification (or two simultaneously) is carried out on an amino-substituted phenylalanine residue in a peptide chain which is a part of a peptidoresin.

GnRH analogs

Methods of making unnatural amino acids are provided which unnatural amino acids can be incorporated into peptides which either inhibit or promote the secretion of gonadotropins by the pituitary gland and inhibit the release of steroids by the gonads. These unnatural amino acids are useful in the synthesis of peptides and have the formula (a): ##STR1## where W is (CH.sub.2) or ##STR2## n is an integer from 1 to 6; j=1, 2 or 3, and preferably, Y is N--CN, X is NH and R.sub.2 is alkyl, modified alkyl, alkenyl, alkynyl, aryl or methyl pyridyl. Disclosed are peptides that are analogs of the decapeptide GnRH wherein there is at least one residue of an unnatural amino acid in the 3-, 5-, 6- and/or 8-positions.

Amino acids and processes for making peptides using same

Methods of making unnatural amino acids are provided which unnatural amino acids can be incorporated into peptides which either inhibit or promote the secretion of gonadotropins by the pituitary gland and inhibit the release of steroids by the gonads. These unnatural amino acids are useful in the synthesis of peptides and have the formula (a): ##STR1## where W is (CH.sub.2).sub.n or ##STR2## n is an integer from 1 to 6; j=1, 2 or 3, and preferably, Y is N--CN, X is NH and R.sub.2 is alkyl, modified alkyl, alkenyl, alkynyl, aryl or methyl pyridyl. Disclosed are peptides that are analogs of the decapeptide GnRH wherein there is at least one residue of an unnatural amino acid in the 3-, 5-, 6- and/or 8-positions.

Preparation of phenylalanine derivatives bearing a 1,2,4-triazole moiety

Analogs of the decapeptide GnRH which include two significantly modified amino acids at positions 5 and 6 inhibit the secretion of gonadotropins by the pituitary gland and inhibit the release of steroids by the gonads. Administration of an effective amount of such GnRH antagonists prevents ovulation of female mammalian eggs and/or the release of steroids by the gonads and may be used to treat steroid-dependent tumors. Particularly effective peptides which are soluble in water at physiologic pH and which have a low tendency to gel when administered in vivo have the following formula:

GNRH antagonists XIII

Unnatural amino acids are provided which can be incorporated into peptides which either inhibit or promote the secretion of gonadotropins by the pituitary gland and inhibit the release of steroids by the gonads. These unnatural amino acids are useful in the synthesis of peptides and have the formula (a): ##STR1## where W is (CH.sub.2).sub.n or ##STR2## n is an integer from 1 to 6; j=1,2 or 3, and preferably, Y is N--CN, X is NH and R.sub.2 is alkyl, modified alkyl, alkenyl, alkynyl, aryl or methyl pyridyl; or the formula (b): ##STR3## where R.sub.11 is H or acyl and W is as defined in (a), and preferably R.sub.11 is H and W is ##STR4## Disclosed are peptides that are analogs of the decapeptide GnRH wherein there is at least one residue of an unnatural amino acid in the 3-, 5-, 6- and/or 8-positions.

Amino acids useful in making GnRH analogs

Peptides which include unnatural amino acids and which either inhibit or promote the secretion of gonadotropins by the pituitary gland and inhibit the release of steroids by the gonads. Administration of an effective amount of such peptides that are GnRH antagonists prevents ovulation of female mammalian eggs and/or the release of steroids by the gonads. The antagonists may be used to treat steroid-dependent tumors, such as prostatic and mammary tumors. The peptides are analogs of the decapeptide GnRH wherein there is at least one residue of an unnatural amino acid in the 3-, 5-, 6- and/or 8-positions. Such unnatural amino acids are useful in the synthesis of peptides and have the formula U.sup.* : ##STR1## where W is (CH.sub.2).sub.n or ##STR2## n is an integer from 1 to 6; and j=1, 2 or 3. Preferably, either Y is N--CN, X is NH and R.sub.2 is alkyl, modified alkyl, alkenyl, alkynyl, aryl or methyl pridyl or ##STR3## where R.sub.11 is H or acyl.

Peptides which include unnatural amino acides and which either inhibit or promote the secretion of gonadotropins by the pituitary gland and inhibit the release of steroids by the gonads. Administration of an effective amount of such peptides that are GnRH antagonists prevents ovulation of female mammalian eggs and/or the release of steroids by the gonads. The antagonists may be used to treat steroid-dependent tumors, such as prostatic and mammary tumors. The peptides are analogs of the decapeptide GnRH wherein there is at least one residue of an unnatural amino acid in the 3-position, the 5-position, the 6-position and/or the 8-position. Such unnatural amino acids are useful in the synthesis of peptides and have the formula U*: ##STR1## where n is an integer from 1 to 6; Y is N--CN, N--CONHR.sub.9, S, O or CH--NO.sub.2 ; R.sub.9 is H, Ac, lower alkyl, aromatic or heterocyclic; X is NH, O, S, M.sub.1 (CH.sub.q).sub.p M.sub.2 or M.sub.1 --(CH.sub.2).sub.p' --M.sub.2 (CH.sub.2).sub.p' --M.sub.3, where M.sub.1 is NR.sub.10, O, S or CHR.sub.3 wherein R.sub.3 is methyl, ethyl, propyl, phenyl, pyridinyl, pyrimidinyl or purinyl, q is 1 or 2; p, p' and p' are integers between O and 6; R.sub.10 is H, lower alkyl or the like, and M.sub.2 and M.sub.3 are M.sub.1, COOH, CONH.sub.2, COOR.sub.3 or CN; R.sub.1 is H, alkyl, modified alkyl, alkenyl, alkynyl, aryl or a direct bond to X; R.sub.2 is R.sub.1, OH, NH.sub.2, NHR.sub.1, or heterocycle.

Methods for making peptides of a suitable length for solid phase synthesis, which peptides include in their sequence a pair of residues of a different character which have acylated side chains and a residue which has an N-alkylated side chain. A peptide intermediate is constructed on the resin using commercially available starting materials. The N-terminus can be acylated by removing the .alpha.-amino protecting group and acylating under standard conditions. First primary amino protecting groups included in those residues to be acylated are removed, and acylation is effected, preferably by using a carboxypyridine or a similar heterocyclic acylating agent. Following such side chain acylation, a second protecting group included in the residue to be N-alkylated is removed, and the N-alkylation reaction is carried out while the peptide remains on the resin using a borohydride and an appropriate aldehyde or ketone. Following cleavage from the resin and removal of any protecting groups still remaining, the peptide is appropriately purified, thus requiring only a single purification to be carried out while forming a synthetic peptide including residues for which the modified amino acids are not readily commercially available.

Growing community of inventors

San Marcos, CA, United States of America

Carl A Hoeger