The crystal structure of the disodium salt of N-phosphorylcreatine hydrate

Abstract

N-Phosphorylcreatine, a biological 'high energy phosphate', serves as an energy reservoir in vertebrate muscles. Crystals of the disodium salt, Na2PN3C4OsHs.4½H20, were prepared. The space group is P21/c, with unit-cell dimensions a= 24.85, b= 6.64, c= 16.94 A and p= 109.5 o and two formula units per asymmetric unit. If a few weak reflections are ignored, the symmetry is that of the space group C2/c with the same unit-cell dimensions and one formula unit per asymmetric unit. The symmetry of the centered cell was assumed and the intensities of 4953 independent reflections were measured with use of balanced filters, Mo Kc( radiation and a Buerger-Supper-Pace automated diffractometer. Sayre's sign relation was used to determine the phases (signs) of 275 reflections and the resulting model was refined by Fourier and least-squares methods to a final R value for observed reflections of 0"083.The guanidino group is planar. All hydrogen atoms available for hydrogen bonding are used and form both inter-and intramolecular bonds. Observed differences between bond distances found in N-phosphorylcreatine and those found in the hydrolysis product creatine are not statistically significant and thus the structural basis of the instability of N-phosphorylcreatine remains unresolved.

Solid‐State Characterization and Transformation of Various Creatine Phosphate Sodium Hydrates

“…Two hydrate forms, H1 and H2, with water contents of 22.0% and 29.7%, respectively, were disclosed in the literature and can be routinely synthesized using an antisolvent crystallization process with water as a good solvent and ethanol as a poor solvent . The crystal structure of H1 has also been reported in the literature . A primary solid‐state screening experiment revealed that multiple hydrate forms exist when different crystallization methods are applied .…”

Crystal and molecular structure of phosphates. 8. The cyclic enediol phosphoimidazole, (C3H3N2)(PO3)(CH3C:CCH3)

“…A collapse of the P(6) intermediate ( 11) with ring opening yields a new P(5)' intermediate ( 12) and then the observed acyclic triester (upon enol-keto tautomerization of 13). The ring-opening step 11 - 12 accounts for the effect of imidazole on the unsymmetrical/symmetrical triesters shown in Table IV. Other experimental observations in support of the P(6) intermediate hypothesis have been previously offered.7-26'44 '46 The demonstrated imidazole catalysis of the reaction CEP-OR + R1OH suggests the possibility that imidazole may also catalyze the reaction CEP-IM (6) + ROH ^CEP-OR + IMH; i.e., the latter reaction could be autocatalytic.…”

A new phosphorus heterocycle. Crystal and molecular structure of 7,8-dimethyl-5-methoxy-5-oxo-.lambda.5-5-phospha-6-oxaindolizine

“…The molecular structure of cyclophosphamide is known.15 Several other structures relevant to the present investigation have also been solved: sodium phosphoramidate,16 P03NH3Na; calcium 1,3-diphosphorylimidazole hexahydrate,17 Cai.sCsHs^tPOs^Ji^O; diphenyl phosphindimethylamidate,18 (C6H5)2P(0)N(CH3)2, trichlorobis(diethylphenylphosphine)(diethylphenylphosphineiminato)ruthenium(IV),19 and phosphocreatine. 20 The nature of the P-N bond has been discussed in those publications and else- Synthesis of 7,8-Dimethyl-5-methoxy-5-oxo-X5-5-phospha-6-oxaindolizine (la). Methanol (0.51 g, 16 mmol) was added to a solution of lV-(l,2-dimethylethenylenedioxyphosphoryl)pyrrole6 (3; 3.22 g, 16 mmol) in anhydrous CH2CI2 (40 mL) at 20 °C.…”