Abstract: 2-(Fluoromethyl or chloromethyl)-2,5-diaminopentanoic acid, 2-(fluoromethyl or chloromethyl)-2,6-diaminohexanoic acid, and 2-fluoromethyl-2-amino-5-guanidinopentanoic acid, and certain derivatives thereof, are inhibitors of ornithine decarboxylase. Methods of preparing the compounds and derivatives are also described.

Abstract: 2-(Fluoromethyl or chloromethyl)-2,5-diaminopentanoic acid, 2-(fluoromethyl or chloromethyl)-2,6-diaminohexanoic acid, and 2-fluoromethyl-2-amino-5-guanidinopentanoic acid, and certain derivatives thereof, are inhibitors of ornithine decarboxylase. Methods of preparing the compounds and derivatives are also described.

Abstract: Novel halomethyl derivatives of .alpha.-amino acids of the following general structure: ##STR1## wherein Y is F.sub.2 CH--, F.sub.3 C--, Cl.sub.2 CH--; Z is .beta.-methylthioethyl, .beta.-thioethyl, .beta.-benzylthioethyl; S-(5'-desoxyadenosin-5'-yl)-S-methylthioethyl, .gamma.-guanidinopropyl, R.sub.a HN(CH.sub.2).sub.n -- wherein n is the integer 3 or 4 or ##STR2## wherein Y.sub.2 is F.sub.2 CH--, or F.sub.3 C--; each of R.sub.a and R.sub.b can be the same or different and is hydrogen, alkylcarbonyl wherein the alkyl moiety has from 1 to 4 carbon atoms and is straight or branched, alkoxycarbonyl wherein the alkoxy moiety has from 1 to 4 carbon atoms and is straight or branched, or ##STR3## wherein R.sub.2 is hydrogen, a straight or branched lower alkyl group of from 1 to 4 carbon atoms, benzyl or p-hydroxybenzyl; R.sub.1 is hydroxy, a straight or branched alkoxy group of from 1 to 8 carbon atoms, --NR.sub.4 R.sub.5 wherein each of R.sub.4 and R.sub.