The crystal and molecular structure of 4-phosphonomethyl-2-oxo-1-piperazinylacetic acid
1989 ◽
Vol 54
(1)
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pp. 160-165
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Keyword(s):
The structure of the title compound was determined by the method of X-ray diffraction of single crystals. The substance crystallizes in the P21/c monoclinic space group. The structure was refined by the least squares method to R = 0.044 on the basis of 2 076 observed reflections. It was found that this compound is not a dicarboxylic acid but rather an intramolecularly cyclized lactam. The hydrogen phosphonato functional group participates in the betain form, while the carboxyl group is not ionized. The conformation of the six-membered oxopiperazine ring is similar to that of cyclohexane in which the peptidic group plays a similar role to the double bond.
1986 ◽
Vol 51
(11)
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pp. 2521-2527
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1972 ◽
Vol 50
(14)
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pp. 2276-2284
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