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Regioselective nitration of N(alpha),N(1)-bis(trifluoroacetyl)-L-tryptophan methyl ester: efficient synthesis of 2-nitro and 6-nitro-N-trifluoroacetyl-L-tryptophan methyl ester.

ABSTRACT: Nitration of N(alpha),N(1)-bis(trifluoroacetyl)-l-tryptophan methyl ester with HNO(3) in acetic anhydride at 0 degrees C provides N(alpha)-trifluoroacetyl-2-nitro-l-tryptophan methyl ester in 67% yield, whereas nitration in trifluoroacetic acid at 0 degrees C gives N(alpha)-trifluoroacetyl-6-nitro-l-tryptophan methyl ester in 69% yield.

SUBMITTER: Osborne AS

PROVIDER: S-EPMC4335804 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature

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Regioselective nitration of N(alpha),N(1)-bis(trifluoroacetyl)-L-tryptophan methyl ester: efficient synthesis of 2-nitro and 6-nitro-N-trifluoroacetyl-L-tryptophan methyl ester.

Osborne Andrew S AS Som Phanneth P Metcalf Jessica L JL Phillips Robert S RS

Bioorganic & medicinal chemistry letters 20080926 21

Nitration of N(alpha),N(1)-bis(trifluoroacetyl)-l-tryptophan methyl ester with HNO(3) in acetic anhydride at 0 degrees C provides N(alpha)-trifluoroacetyl-2-nitro-l-tryptophan methyl ester in 67% yield, whereas nitration in trifluoroacetic acid at 0 degrees C gives N(alpha)-trifluoroacetyl-6-nitro-l-tryptophan methyl ester in 69% yield. ...[more]

PMID: 18851915

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