- Tetrapyrrole aminocarboxylic acids
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A fluorescent mono-, di-, or tri- or tetramide between an amino acid of the formula STR1 and a carboxy containing tetrapyrrole of the formula: STR2 or the corresponding di or tetrahydrotetrapyrroles. The compounds herein are useful for the photodetection and phototreatment of tumors and/or cancerous tissues in animal hosts.
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- Gas Chromatography-Mass Spectrometry of Trimethylsilylated Imino Derivatives of Alanine
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Trimethylsilylation of seven imino derivatives of alanine with N,O-bis(trimethylsilyl)trifluoroacetamide in acetonitrile was studied.The imino derivatives include 2,2'-iminodipropionitrile (1), 2,2'-iminodipropionamide (2), 2,2'-iminodipropionic acid (3), 2-(1-cyanoethylamino)propionamide (4), 2-(1-cyanoethylamino)propionic acid (5), 2-(1-carbamoylethylamino)propionic acid (6), and 3,5-dimethyl-2,6-piperazinedione (7).The reaction products were identified by gas chromatography-mass spectrometry.Under the present reaction conditions (at 100 deg C for 30 min), hydrogen atoms of carboxyl and carbamoyl groups and an imide hydrogen were readily replaced by the trimethylsilyl (TMS) group, but imino hydrogens were not replaced bacause of the steric hindrance of N-substituent group.For the carbamoyl group, only one hydrogen was replaced.Consequently, 1 was not trimethylsilylated.Furthermore, no definite trimethylsilylation products were obtained for 4.Upon electron impact at 70 eV, 2, 3, and 5-7 gave rather simple spectra with molecular (M+) and M-15 (loss of CH3) ions characteristic of TMS derivatives.A fragment, M-117 (loss of COOTMS) or M-116 (loss of CONHTMS), was very prominent for 2, 3, 5, and 6.Other important ions such as m/z 70 were noted.Preparations and properties of some of the imino derivatives are also described.
- Kawashiro, Katsuhiro,Morimoto, Shiro,Yoshida, Hideyuki
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p. 1903 - 1912
(2007/10/02)
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- Mass Spectra of Butyl Esters and N-Trifluoroacetyl Butyl Esters of Some Iminodicarboxylic Acids upon Electron Impact
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Mass spectra (electron impact at 20 eV) of butyl esters and N-trifluoroacetyl (TFA) butyl esters of some iminodicarboxylic acids (IDCAs) were determined by gas chromatography-mass spectrometry.The IDCAs included iminodiacetic acid (1), 2-(carboxymethylamino)propionic acid (2), 3-(carboxymethylamino)propionic acid (3), 2,2'-iminodipropionic acid (4), 2,3'-iminodipropionic acid (5), 3,3'-iminodipropionic acid (6), N-methylaminodiacetic acid (7), and nitrilotriacetic acid (8).The mass spectra of the butyl ester derivatives are simple, exhibiting the corresponding molecular (M+) ions with the exception of 5.The α,α'-IDCAs (1, 2, 4, 7, and 8) are characterized by M+, M -101 (COOC4H9) (base peak), and M - 157 (COOC4H9 + C4H8) ions.The β,β'-IDCA (6) is characterized by a more complex spectrum with M+, M - 73 (OC4H9), M - 115 (CH2COOC4H9) (base peak), M - 129 (OC4H9 + C4H9), and M - 171 (CH2COOC4H9 + C4H9) ions.The α,β'-IDCAs (3 and 5) in general show spectra in which both ions characteristic of α,α'- and β,β'-IDCAs are observed.The addition of TFA to the imino nitrogens of 1 - 6 increases complexity of the resulting spectra.In these instances, although M+ ions are usually present, neither M - 101 nor 115 ions are base peaks.The fragmentation pathways of these two volatile derivatives of the IDCAs upon electron impact are discussed.
- Kawashiro, Katsuhiro,Morimoto, Shiro,Yoshida, Hideyuki
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p. 1097 - 1103
(2007/10/02)
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- SYNTHESE D'AMINODIACIDES
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A general method for the synthesis of a new aminodiacids (4) by aminodiesters (3) hydrolysis is presented.
- Garrigues, Bernard
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p. 1151 - 1156
(2007/10/02)
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- Preparation of DL-Alanine by the Reaction of (+/-)-2-Chloropropionic Acid with Aqueous Ammonia under Pressure
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The effects of experimental conditions (molar ratio of reactans, concentration, temperature, and pressure) on the yield of DL-alanine produced by the reaction of (+/-)-2-chloropropionic acid with aqueous ammonia have been studied.Molar ratio of NH3 : CH3CHClCO2H (ca. 10:1 ) much lower than that reported in the literature (68:1) can give a comparable yield (ca. 78 percent) by the reaction under pressure at 70 deg C for 5 h, a much shorter time than that reported in literature (over 96 h).Addition of ammonium carbonate does not increase the yield against the literature.
- Ogata, Yoshiro,Inaishi, Morio
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p. 3605 - 3606
(2007/10/02)
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