Dumas, Stephane published the artcileHigh relaxivity magnetic resonance imaging contrast agents part 1: impact of single donor atom substitution on relaxivity of serum albumin-bound gadolinium complexes, Recommanded Product: Diethyl (bromomethyl)phosphonate, the publication is Investigative Radiology (2010), 45(10), 600-612, database is CAplus and MEDLINE.
Rationale and objectives: The donor atoms that bind to gadolinium in contrast agents influence inner-sphere water exchange and electronic relaxation, both of which determine observed relaxivity. The effect of these mol. parameters on relaxivity is greatest when the contrast agent is protein bound. We sought to determine an optimal donor atom set to yield high relaxivity compounds Methods: A total of 38 gadolinium-1,4,7,10-tetraazacyclo-dodecane-N,N’,N”,N”’-tetraacetato derivatives were prepared and relaxivity was determined in the presence and absence of human serum albumin as a function of temperature and magnetic field. Each compound had a common albumin-binding group and differed only by substitution of different donor groups at one of the macrocycle nitrogens. Oxygen-17 isotope relaxometry at 7.05 T was performed to estimate water exchange rates. Results: Changing a single donor atom resulted in changes in water exchange rates ranging across 3 orders of magnitude. Donor groups increased water exchange rate in the order: phosphonate ∼ phenolate > α-substituted acetate > acetate > hydroxamate ∼ sulfonamide > amide ∼ pyridyl ∼ imidazole. Relaxivites at 0.47 and 1.4 T, 37°C, ranged from 12.3 to 55.6 mMs and from 8.3 to 32.6 mMs resp. Optimal relaxivities were observed when the donor group was an α-substituted acetate. Electronic relaxation was slowest for the acetate derivatives as well. Conclusions: Water exchange dynamics and relaxivity can be predictably tuned by choice of donor atoms.
Investigative Radiology published new progress about 66197-72-6. 66197-72-6 belongs to bromides-buliding-blocks, auxiliary class Aliphatic Chain, name is Diethyl (bromomethyl)phosphonate, and the molecular formula is C5H12BrO3P, Recommanded Product: Diethyl (bromomethyl)phosphonate.
Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary