Abstract
Two simple and efficient synthetic methods for the preparation of semicarbazide amino acid derivatives are reported. The procedures involve reaction between the carbamoyl azides of α-N-protected amino acids and hydrazine monohydrate: 4-[(alkoxycarbonylamino)(alkyl)methyl]semicarbazides 1 are obtained when hydrazine is added to the separated tetrahydrofuran (THF) solution containing the carbamoyl azide at 0 °C, whereas 1-[(alkoxycarbonylamino)(alkyl)methyl-carbamoyl]-4-[(alkoxycarbonylamino)(alkyl) methyl]semicarbazides 4 are produced by adding hydrazine directly into the final THF/aqueous buffer (KH2PO4) biphasic mixture containing the prepared carbamoyl azide at 50 °C, respectively. NMR experimental data obtained from samples dissolved in [D6]dimethyl sulfoxide suggest a dimeric association for semicarbazides 4 with intermolecular hydrogen bonds. Moreover, the ESI-MS-MS spectra reveal some interesting common features.
Original language | English (US) |
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Pages (from-to) | 1376-1384 |
Number of pages | 9 |
Journal | European Journal of Organic Chemistry |
Issue number | 7 |
DOIs | |
State | Published - Mar 2011 |
Keywords
- Amino acids
- Azides
- Semicarbazides
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry