Abstract: New peptides are disclosed which have biological activity of the same type as known calcitonins and which have a longer amino acid chain than natural calcitonins, specifically, the peptide chain of the disulfide ring is enlarged. Also resin peptides are disclosed which may be converted to peptides having such biological activity; and processes for producing said resin peptides and said calcitonin peptides.

Abstract: Two new peptides are disclosed which have biological activity of the same type as known calcitonins, which have a shorter amino acid chain than natural calcitonins and which are substitution analogs of the natural calcitonins. Also resin peptides are disclosed which may be converted to peptides having such biological activity; and processes for producing said resin peptides and said calcitonin peptides.

Abstract: Two new peptides are disclosed which have biological activity of the same type as known calcitonins and which have a shorter amino acid chain than natural calcitonins and are also substitution analogs of the natural calcitonins. Also resin peptides are disclosed which may be converted to peptides having such biological activity; and processes for producing said resin peptides and said calcitonin peptides.

Abstract: New peptides are disclosed which have biological activity of the same type as known calcitonins and which have a D-amino acid in position 24 instead of the natural L-amino acid. Also resin peptides are disclosed which may be converted to peptides having such biological activity, and processes for producing said resin peptides and said calcitonin peptides.

Abstract: Two new peptides are disclosed which have biological activity of the same type as known calcitonins and which have a shorter amino acid chain than natural calcitonins. Also resin peptides are disclosed which may be converted to peptides having such biological activity; and processes for producing said resin peptides and said calcitonin peptides.

Abstract: The purification of crude calcitonin by subjecting a crude calcitonin material to partition chromatography in which the solvent utilized is a mixture of butanol, a lower aliphatic alcohol, which is ethanol, methanol, or propanol, or mixtures thereof, acetic acid, water and ammonium acetate. In place of acetic acid and ammonium acetate, formic acid and ammonium formate may be used. The crude calcitonin of this invention is of a type known as ultimobronchial calcitonin. This includes calcitonins of the salmon and eel, whether the calcitonins of this type be obtained from natural sources or are prepared by synthesis.

Abstract: New peptides are disclosed which have biological activity of the same type as known calcitonins which have both a D-amino acid in position 24 instead of the natural L-amino acid and are substitution analogs of the natural calcitonins. Also resin peptides are disclosed which may be converted to peptides having such biological activity; and processes for producing said resin peptides and said calcitonin peptides.

Abstract: New peptides are disclosed which have biological activity of the same type as known calcitonins and which are substitution analogs of the natural calcitonins. Also resin peptides are disclosed which may be converted to peptides having such biological activity; and processes for producing said resin peptides and said calcitonin peptides.

Abstract: Two new peptides are disclosed which have biological activity of the same type as known calcitonins and which are substitution analogs of natural calcitonins. Also resin peptides are disclosed which may be converted to peptides having such biological activity; and processes for producing said resin peptides and said calcitonin peptides.

Abstract: Peptides are disclosed which have biological activity of the same type as known calcitonins and which have a shorter amino acid chain than natural calcitonins. Also resin peptides are disclosed which may be converted to peptides having such biological activity; and processes for producing said resin peptides and said calcitonin peptides.

Abstract: New peptides are disclosed which have biological activity of the same type as known calcitonins and which have a shorter amino acid chain than natural calcitonins. Also resin peptides are disclosed which may be converted to peptides having such biological activity; and processes for producing said resin peptides and said calcitonin peptides.

Abstract: The purification of crude calcitonin by subjecting a crude calcitonin material to partition chromatography in which the solvent utilized is a mixture of butanol, a lower alphatic alcohol which is ethanol, methanol, or propanol, or mixtures thereof, acetic acid, water and ammonium acetate. The crude calcitonin of this invention is of a type known as ultimobronchial calcitonin. This includes calcitonins of the salmon and eel, whether the calcitonins of this type be obtained from natural sources or are prepared by synthesis. Preferably, the crude calcitonins of this type, which are purified by the process herein set forth, are obtained by solid phase synthesis in which the amino acid chain is assembled by attaching a resin support to the first amino acid, adding the amino acids one-by-one in the order in which they appear in the natural calcitonin; and finally removing the resin and the protective groups used in the synthesis.

Abstract: A new peptide which has calcitonin-like biological activity which has a shorter amino acid chain and which is chemically more stable than natural calcitonins. Also resin peptides are disclosed which may be converted to peptides having biological activity and processes for producing said resin peptides and said peptides having biological activity.

Abstract: A new peptide which has calcitonin-like biological activity which has a shorter amino acid chain and which is chemically more stable than natural calcitonins. Also resin peptides are disclosed which may be converted to peptides having biological activity and processes for producing said resin peptides and said peptides having biological activity.

Abstract: A new peptide is disclosed which has biological activity of the same type as known calcitonins and which has a shorter amino acid chain than natural calcitonins. Also resin peptides are disclosed which may be converted to peptides having such biological activity; and processes for producing said resin peptides and said calcitonin peptides.

Abstract: The synthesis of a disulfide cyclic peptide by preparing an intermediate peptide containing two cysteine moieties, each of which is protected by an n-alkylthio group, or when one of such moieties is in an amino terminal position, this one moiety may be protected by a cysteine group while the other is protected by an n-alkylthio group, and placing such intermediate peptide in a solution substantially free of oxygen and preferably at a pH of from 5 to 10 until rearrangement has taken place, to yield a cyclic disulfide peptide. The disclosure also embraces said intermediate peptides as new compounds and the processes by which they are prepared.

Abstract: The synthesis of a disulfide cyclic peptide by preparing an intermediate peptide containing an amino terminal cystine residue and a cysteine residue located in a position within the amino acid sequence, to give a desired peptide, and placing such intermediate peptide in a solution substantially free of oxygen at a pH of from about 5 to 10 until rearrangement takes place to yield a cyclic disulfide peptide and to displace a molecule of cysteine from the amino terminal cysteine residue. The disclosure also embraces said intermediate peptides as new compounds and the processes by which they are prepared.