Patent ID: 7122519

Claim:
A method of performing a function selected from the group consisting of I) inhibiting protein synthesis in a cell, II) inhibiting growth of a cell, III) inhibiting proliferation of a cell, IV) inhibiting tumorigenesis in a cell, and V) enhancing apoptosis of a cell, the method comprising administering to the cell a didemnin analog having the structure wherein: i) R 1 is selected from the group consisting of —H, -(tert-butyloxycarbonyl), -leucine, —(N-methyl)leucine, —(N-methyl)leucine-proline, —(N-methyl)leucine-proline-lactate, —(N-methyl)leucine-proline-pyruvate, —(N-methyl)leucine-proline-lactate-(a first fluorophore), —(N-methyl)leucine-proline-lactate-glutamine-pyroglutamate, —(N-methyl)leucine-proline-lactate-glutamine-cyclopentanoate, —(N-methyl)leucine-proline-alanine-leucine-pyroglutamate, and —(N-methyl)leucine-proline-(N-methyl-alanine)-leucine-pyroglutamate; ii) R 2 and R 3 are one of (a) R 2 is selected from the group consisting of an isoleucine side chain, a valine side chain, an alanine side chain, a norleucine side chain, a norvaline side chain, a leucine side chain, a histidine side chain, a tryptophan side chain, an arginine side chain, a lysine side chain, a second fluorophore, and a substituent having the structure and R 3 is selected from the group consisting of —CH 3 and —H; or (b) R 2 and R 3 together form the structure iii) each of R 5 , R 6 , R 7 , R 8 , and R 9 , when present, is independently selected from the group consisting of —H, —OH, —OCH 3 , —CO(C 6 H 5 ), —Br, —I, —F, —Cl, —CH 3 , and —C 2 H 5 ; iv) R 4 is selected from the group consisting of an isoleucine side chain and a valine side chain; v) X is selected from the group consisting of —O— and —NH—; vi) Y is selected from the group consisting of —H and a hydroxyl protecting group; vii) R 10 is selected from the group consisting of a leucine side chain and a lysine side chain; and viii) the molecule is not tamandarin A and is not tamandarin B (compound 105).