The tetradecapaptides of the formula ##STR1## wherein X is H-Ala-D-Ala, H-D-Ala-Gly, or H-D-Val-Gly, or the non-toxic, pharmaceutically acceptable acid addition salts thereof; inhibit the secretion of growth hormone, while not materially inhibiting the secretion of insulin or glucagon. Intermediates used in the synthesis of the tetradecapeptides are also described.

Tetradecapeptides of the formula ##STR1## wherein X is H-Ala-D-Ala, H-D-Ala-Gly, or H-D-Val-Gly, and X.sup.1 is Phe or Cha, or a non-toxic pharmaceutically acceptable acid addition salt thereof, inhibit the secretion of growth hormone without materially inhibiting the secretion of glucagon or insulin. Intermediates and processes for making the tetradecapeptides are also described.

The tetradecapeptides of the formula ##STR1## wherein X is H--Ala--D--Ala, H--D--Ala--Gly, or H--D--Val--Gly; and X is Ala--Leu, Ala--Phe, Ala--D--Phe, D--Ala--Phe, or D--Ala--Cha; or the non-toxic, pharmaceutically acceptable acid addition salts thereof; inhibit secretion of growth hormone, while not materially inhibiting the secretion of insulin or glucagon. Intermediates used in the synthesis of the tetradecapeptides are also described.

Polypeptides of the formula: ##STR1## and the reduced linear form thereof, wherein X is H, Ala-Gly-, Ala-D-Ala, Gly-Gly-Gly-, acetyl or benzoyl; X.sub.4 is Arg or His; X.sub.8 is Trp or D-Trp; X.sub.14 is Cys or D-Cys, or a non-toxic acid addition salts thereof, inhibit the secretion of growth hormone, insulin and glucagon.

4'-Deoxyvincristine, 4'-deoxy-1-formylleurosidine and the corresponding 4-desacetyl derivatives, useful in inhibiting the growth of experimental tumors.

Compounds of the formula: ##STR1## wherein: X is H, Ala-Gly, Gly-Gly-Gly, Ala-D-Ala, acetyl, or benzoyl; X.sub.1 is Arg or His; X.sub.2 is Glu or Asp; X.sub.3 is Trp or D-Trp; or 6-F-D-Trp; and X.sub.4 is Cys- or D-Cys; or a non-toxic pharmaceutically acceptable acid addition salt thereof; inhibit the secretion of growth hormone and glucagon without materially affecting the secretion of insulin.

A process for preparing vincamine and related alkaloids, comprising reacting a compound of formula: ##STR1## (wherein R is H or methoxy and X and Y are hydrogen or together represent a double bond between the carbon atoms to which they are bonded) with a carbanion-forming agent in a reaction medium; then introducing oxygen into the reaction medium until saturation point, a reducing agent compatible with oxygen being added to the reaction medium before the medium ceases absorbing oxygen; acidifyi...

New phosphonoacyl prolines and related compounds have the general formula ##STR1## wherein R.sub.1 and R.sub.2 each is hydrogen, lower alkyl, lower alkenyl, unsustituted or substituted phenyl-lower alkyl, or a metal ion; R.sub.3 is hydrogen or lower alkyl; R.sub.4 is hydrogen, lower alkyl, phenyl-lower alkyl or a metal ion; and N is 0 or 1. These compounds are useful as hypotensive agents.

Polypeptides of the formula: ##STR1## and the reduced linear form thereof, wherein: X.sub.1 is Arg or His; X.sub.2 is His, Tyr, or Glu; X.sub.3 is Trp or D-Trp; or 6-F-D-Trp X.sub.4 is ##STR2## n is 1, 2, 3, or 4; and m is 1 or 2; or the non-toxic acid addition salts thereof, inhibit the secretion of growth hormone and glucagon without materially affecting the secretion of insulin.

Provided is a benzoylphenylalanine of the formula: ##STR1## wherein ##STR2## is in the m or p position; and Pr is a protecting group which is easily cleavable in the presence of a peptide bond by a mild acid or base. This benzoylphenylalanine group is incorporated into a peptide chain which can be attached to a solid substrate having a reactive hydrogen by exposure to low energy ultraviolet light.