1012802-95-7Relevant academic research and scientific papers
Practical Synthesis of a Stable Precursor for Positron Emission Tomography Imaging Agent 18F-GTP1
Clagg, Kyle,Gosselin, Francis,Lim, Ngiap-Kie,Nack, William A.,O'Shea, Paul D.,Sirois, Lauren E.,White, Nicholas A.,Zhang, Haiming
, p. 1690 - 1699 (2020)
18F-GTP1 is a deuterated small molecule positron emission tomography (PET) imaging agent used to visualize tau tangles in Alzheimer's disease patients. The first-generation synthesis of 18F-GTP1's nonradiolabeled alkyl tosylate precursor was plagued by low-yielding steps, inefficient chromatographic purifications, and variable product quality. Due to these limitations, a more robust second-generation route was developed and successfully executed on kilogram scale. A reduction with LiAlD4 incorporated geminal deuterium atoms, while an efficient amidation reaction accessed the key acrylamide coupling partner. Moreover, the tricyclic imidazo[1,2-a]pyrimidine core was assembled via a novel, convergent, and highly selective phosphoramidate-directed annulation. The improved synthesis eliminated all chromatography en route to a high-yielding and reproducible acid-promoted tosylation as the final step.
2-PHENYL-3,4-DIHYDROPYRROLO[2,1 -F] [1,2,4]TRIAZINONE DERIVATIVES AS PHOSPHODIESTERASE INHIBITORS AND USES THEREOF
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Page/Page column 90; 91, (2017/07/14)
The present invention relates to compounds of formula (I) or pharmaceutically acceptable salt, solvate or hydrate thereof, wherein R1 is C1-C3alkyl optionally substituted with F, C3-C6cycloalkyl, C1-C3alkoxy; X represents a bond or C1-C3alkylene optionally substituted with OH, ONO, ONO2; R2 is H, OH, ONO, ONO2, C(O)OH, C(O)OC1-C3alkyl, CHO, CN, C1-C3alkoxy, OC(O)H, OC(O)-C1-C3alkyl, C(O)N(R6)OR7, OC1-C3alkylene-C(O)OH, OC1-C3alkylene-C(O)OC1-C3alkyl, OC1-C3alkylene-C(0)N(R6)OR7, S(O0-2)C1-C3alkyl, CR8=N-OR9, CR8=N-NR10R11, CR8=NR12 or CR8=N-ONO2; R3 is C1-C6alkyl optionally substituted with F, OH, ONO, ONO2, C1-C3alkoxy, C3-C6cycloalkyl; C3-C6cycloalkyl, C2-C6alkenyl, C2-C6alkynyl; R4 is C1-C6alkyl optionally substituted with C3-C6cycloalkyl, C1-C6alkoxy, F, ONO, ONO2; C2-C6alkenyl, C2-C6alkynyl, C3-C6cycloalkyl; R5 is H, SO2NR13R14, NHSO2NR13R14; R6 is H or C1-C3alkyl; R7 is H, C1-C3alkyl, C1-C3alkoxy, C1-C3alkyl substituted with phenyl, benzyl or a heterocyclic ring, wherein said phenyl, benzyl or said heterocyclic ring are independently optionally substituted by C1-C3alkyl, F; R8 is H, CH3 or C2H5; R9: H, C1-C3alkyl optionally substituted with OH, ONO, ONO2, CN, COOH, COOC1-C3alkyl, C1-C3alkoxy, OC(O)H, OC(O)-C1-C3alkyl, C(O)N(R6)OR7, OC1-C3alkylene-C(O)OH, OC1-C3alkylene-C(O)OC1-C3alkyl, OC1-C3alkylene-C(O)N(R6)OR7, S(O0-2)C1-C3alkyl; R10 and R11 are each independently H, C1-C3alkyl optionally substituted with OH, ONO, ONO2, CN, COOH, COOC1-C3, C1-C3alkoxy, OC(O)H, OC(O)-C1-C3alkyl, C(O)N(R6)OR7, OC1-C3alkylene-C(O)OH, OC1-C3alkylene-C(O)OC1-C3alkyl, OC1-C3alkylene-C(O)N(R6)OR7, S(O0-2)C1-C3alkyl;i or together with the nitrogen atom to which they are attached form a heterocyclic ring, wherein preferably said heterocyclic ring is selected from aziridine, azetidine, pyrollidine, piperidine, morpholine, piperazine and homopiperazine, wherein said heterocyclic ring is optionally substituted with C1-C3 alkyl; R12 is C1-C3 alkyl optionally substituted with OH, ONO, ONO2, CN, COOH, COOC1-C3alkyl, C1-C3alkoxy, OC(O)H, OC(O)-C1-C3alkyl, C(O)N(R6)OR7, OC1-C3alkylene-C(O)OH, OC1-C3alkylene-C(O)OC1-C3alkyl, OC1-C3alkylene-C(O)N(R6)OR7, S(O0-2)C1-C3alkyl; R13 and R14 are each independently H or C1-C6alkyl optionally substituted with F, OH, ONO, ONO2, COOH, C1-C3alkoxy, C3-C6Cycloalkyl; or together with the nitrogen atom to which they are attached form a heterocyclic ring, wherein preferably said heterocyclic ring is selected from aziridine, azetidine, pyrollidine, piperidine, morpholine, piperazine, homopiperazine, 2,5-diazabicyclo[2,2,1]heptane and 3,7-diazabicyclo[3,3,0]octane, wherein said heterocyclic ring is optionally substituted with R15; R15 is C1-C6alkyl optionally substituted with halogen, OH, ONO, ONO2, C1-C3alkoxy, C1-C3haloalkoxy, COOR16, NR17R18, C=NR19, or with a tetrazole group which is optionally substituted with C1-C3alkyl; or a heteroaryl ring which is optionally substituted with F, wherein the at least one heteroatom of said heteroaryl ring is nitrogen; R16 is H, or C1-C4alkyl optionally substituted with F, OH, ONO, ONO2, NR17R18, or with a heteroaryl ring, wherein the at least one heteroatom of said heteroaryl ring is nitrogen, and wherein preferably said heteroaryl ring is selected from pyrrolidine, piperidine, piperazine, morpholine, pyrrole, and imidazole, wherein nitrogen atom is directly bound to C1-C4 alkyl; R17 and R18 are each independently H or C1-C4alkyl optionally substituted with ONO, ONO2; R19 is C1-C4alkyl optionally substituted with F, ONO, ONO2; C3-C6Cycloalkyl; and their use in methods of treating or preventing a disease alleviated by inhibition of PDE-5 in a human or in a non-human mammal.
μ-Oxo-Dinuclear-Iron(III)-Catalyzed O-Selective Acylation of Aliphatic and Aromatic Amino Alcohols and Transesterification of Tertiary Alcohols
Horikawa, Rikiya,Fujimoto, Chika,Yazaki, Ryo,Ohshima, Takashi
, p. 12278 - 12281 (2016/08/24)
A highly chemoselective and reactive μ-oxo-dinuclear iron(III) salen catalyst for transesterification was developed. The developed iron complex catalyzed acylation of aliphatic amino alcohols with nearly perfect O-selectivity, even when using activated esters, for which chemoselectivity is more difficult to control. In addition, O-selective transesterification of aromatic amino alcohols was achieved for the first time. The high activity of the iron complex enabled the use of sterically congested tertiary alcohols, including unprecedented tert-butanol.
Enzyme-like chemoselective acylation of alcohols in the presence of amines catalyzed by a tetranuclear zinc cluster
Ohshima, Takashi,Iwasaki, Takanori,Maegawa, Yusuke,Yoshiyama, Asako,Mashima, Kazushi
, p. 2944 - 2945 (2008/09/20)
Acylation of alcohols and amines is one of the most fundamental reactions. Due to the greater nucleophilicity of the amino group compared to the hydroxyl group, complete N-acylation occurs. Only an enzymatic reaction can promote a highly selective O-acyla
