Synthesis and biological evaluation of pyrazolo[1,5-a]-pyrimidine-containing 99mTc Nitrido radiopharmaceuticals as imaging agents for tumors.
The compound 5-((2-aminoethylamino)methyl)-7-(4-bromoanilino)-3-cyano-pyrazolo[1,5-a]pyrimidine (ABCPP) was synthesized and conjugated with N-mercapto-acetylglycine (MAG), N-mercaptoacetylphenylalanine (MAF) and N-mercaptoacetylvaline (MAA), respectively. These three compounds were labeled successfully with [99mTcN]2+ intermediate in high radiochemical purities. Biodistribution in tumor-bearing mice demonstrated that the three new complexes showed tumor accumulation, high tumor-to-muscle (T/M) ratios and fast clearance from blood and muscle. Among them, the 99mTcN-MAG-ABCPP showed the most favorable characteristics, with tumor/blood and tumor/ muscle ratios reaching 1.51 and 2.97 at 30 min post-injection, 1.84 and 2.49 at 60 min post-injection, suggesting it could be further studied as potential tumor imaging agent for single photon emission computed tomography (SPECT).
Key Laboratory of Radiopharmaceuticals, College of Chemistry, Beijing Normal University, Beijing 100875, China. dingrui@mail.bnu.edu.cn
Rui
R
Ding
Yong
Y
He
Jingli
J
Xu
Hang
H
Liu
Xiao
X
Wang
Man
M
Feng
Chuanmin
C
Qi
Junbo
J
Zhang
D000818:Animals; D005260:Female; D051379:Mice; D009374:Neoplasms, Experimental / Q000000981:diagnostic imaging*; D011720:Pyrazoles / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D011743:Pyrimidines / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D011859:Radiography; D019275:Radiopharmaceuticals / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D013667:Technetium / Q000737:chemistry*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
D011720:Pyrazoles; D011743:Pyrimidines; D019275:Radiopharmaceuticals; D013667:Technetium