Novel Pyrazolo[1,5-a]pyrimidines as Translocator Protein 18 kDa (TSPO) Ligands: Synthesis, in Vitro Biological Evaluation, [18F]-Labeling, and in Vivo Neuroinflammation PET Images

Zingiber zerumbetSm., locally known to the Malay as “Lempoyang,” is a perennial herb found in many tropical countries, including Malaysia. The rhizomes ofZ. zerumbet, particularly, have been regularly used as food flavouring and appetizer in various Malays' cuisines while the rhizomes extracts have been used in Malay traditional medicine to treat various types of ailments (e.g., inflammatory- and pain-mediated diseases, worm infestation and diarrhea). Research carried out using differentin vitroandin vivoassays of biological evaluation support most of these claims. The active pharmacological component ofZ. zerumbetrhizomes most widely studied is zerumbone. This paper presents the botany, traditional uses, chemistry, and pharmacology of this medicinal plant.

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Optimised GMP-compliant production of [18F]DPA-714 on the Trasis AllinOne module

EJNMMI Radiopharmacy and Chemistry ◽

10.1186/s41181-021-00133-0 ◽

2021 ◽

Vol 6 (1) ◽

Author(s):

Klaudia A. Cybulska ◽

Vera Bloemers ◽

Lars R. Perk ◽

Peter Laverman

Keyword(s):

Significant Degree ◽

Translocator Protein ◽

Positron Emission ◽

Leaving Group ◽

Inflammatory Processes ◽

Single Production ◽

Translocator Protein 18 Kda ◽

Radiochemical Yields ◽

Specific Ligand

Abstract Background The translocator protein 18 kDa is recognised as an important biomarker for neuroinflammation due to its soaring expression in microglia. This process is common for various neurological disorders. DPA-714 is a potent TSPO-specific ligand which found its use in Positron Emission Tomography following substitution of fluorine-19 with fluorine-18, a positron-emitting radionuclide. [18F]DPA-714 enables visualisation of inflammatory processes in vivo non-invasively. Radiolabelling of this tracer is well described in literature, including validation for clinical use. Here, we report significant enhancements to the process which resulted in the design of a fully GMP-compliant robust synthesis of [18F]DPA-714 on a popular cassette-based system, Trasis AllinOne, boosting reliability, throughput, and introducing a significant degree of simplicity. Results [18F]DPA-714 was synthesised using the classic nucleophilic aliphatic substitution on a good leaving group, tosylate, with [18F]fluoride using tetraethylammonium bicarbonate in acetonitrile at 100∘C. The process was fully automated on a Trasis AllinOne synthesiser using an in-house designed cassette and sequence. With a relatively small precursor load of 4 mg, [18F]DPA-714 was obtained with consistently high radiochemical yields of 55-71% (n=6) and molar activities of 117-350 GBq/µmol at end of synthesis. With a single production batch, starting with 31-42 GBq of [18F]fluoride, between 13-20 GBq of the tracer can be produced, enabling multi-centre studies. Conclusion To the best of our knowledge, the process presented herein is the most efficient [18F]DPA-714 synthesis, with advantageous GMP compliance. The use of a Trasis AllinOne synthesiser increases reliability and allows rapid training of production staff.

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Photoelectric Dye, NK-5962, as a Potential Drug for Preventing Retinal Neurons from Apoptosis: Pharmacokinetic Studies Based on Review of the Evidence

Life ◽

10.3390/life11060591 ◽

2021 ◽

Vol 11 (6) ◽

pp. 591

Author(s):

Toshihiko Matsuo ◽

Shihui Liu ◽

Tetsuya Uchida ◽

Satomi Onoue ◽

Shinsaku Nakagawa ◽

...

Keyword(s):

Biological Evaluation ◽

Pharmacokinetic Studies ◽

Retinal Neurons ◽

Retinal Cells ◽

Intravitreous Injection ◽

Rcs Rats ◽

Photoelectric Dye ◽

Dark Conditions

NK-5962 is a key component of photoelectric dye-based retinal prosthesis (OUReP). In testing the safety and efficacy, NK-5962 was safe in all tests for the biological evaluation of medical devices (ISO 10993) and effective in preventing retinal cells from death even under dark conditions. The long-term implantation of the photoelectric dye-coupled polyethylene film in the subretinal space of hereditary retinal dystrophic (RCS) rats prevented neurons from apoptosis in the adjacent retinal tissue. The intravitreous injection of NK-5962 in the eyes of RCS rats, indeed, reduced the number of apoptotic cells in the retinal outer nuclear layer irrespective of light or dark conditions. In this study, we reviewed the in vitro and in vivo evidence of neuroprotective effect of NK-5962 and designed pharmacokinetic experiments. The in vitro IC50 of 1.7 μM, based on the protective effect on retinal cells in culture, could explain the in vivo EC50 of 3 μM that is calculated from concentrations of intravitreous injection to prevent retinal neurons from apoptosis. Pharmacokinetics of NK-5962 showed that intravenous administration, but not oral administration, led to the effective concentration in the eye of rats. NK-5962 would be a candidate drug for delaying the deterioration of retinal dystrophy, such as retinitis pigmentosa.

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New Antiparasitic Flexible Triaryl Diamidines, their Prodrugs and Aza Analogues: Synthesis, in Vitro and in Vivo Biological Evaluation, and Molecular Modelling Studies

European Journal of Medicinal Chemistry ◽

10.1016/j.ejmech.2021.113625 ◽

2021 ◽

pp. 113625

Author(s):

Reem K. Arafa ◽

Mohamed A. Ismail ◽

Tanja Wenzler ◽

Reto Brun ◽

Ananya Paul ◽

...

Keyword(s):

Molecular Modelling ◽

Biological Evaluation ◽

Molecular Modelling Studies ◽

Modelling Studies

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Development of 18F-Labeled Radiotracers for PET Imaging of the Adenosine A2A Receptor: Synthesis, Radiolabeling and Preliminary Biological Evaluation

International Journal of Molecular Sciences ◽

10.3390/ijms22052285 ◽

2021 ◽

Vol 22 (5) ◽

pp. 2285

Author(s):

Thu Hang Lai ◽

Susann Schröder ◽

Magali Toussaint ◽

Sladjana Dukić-Stefanović ◽

Mathias Kranz ◽

...

Keyword(s):

Specific Binding ◽

Brain Slices ◽

Total Activity ◽

Biological Evaluation ◽

Adenosine A2a Receptor ◽

Positron Emission ◽

A2a Receptor ◽

Adenosine A2a

The adenosine A2A receptor (A2AR) represents a potential therapeutic target for neurodegenerative diseases. Aiming at the development of a positron emission tomography (PET) radiotracer to monitor changes of receptor density and/or occupancy during the A2AR-tailored therapy, we designed a library of fluorinated analogs based on a recently published lead compound (PPY). Among those, the highly affine 4-fluorobenzyl derivate (PPY1; Ki(hA2AR) = 5.3 nM) and the 2-fluorobenzyl derivate (PPY2; Ki(hA2AR) = 2.1 nM) were chosen for 18F-labeling via an alcohol-enhanced copper-mediated procedure starting from the corresponding boronic acid pinacol ester precursors. Investigations of the metabolic stability of [18F]PPY1 and [18F]PPY2 in CD-1 mice by radio-HPLC analysis revealed parent fractions of more than 76% of total activity in the brain. Specific binding of [18F]PPY2 on mice brain slices was demonstrated by in vitro autoradiography. In vivo PET/magnetic resonance imaging (MRI) studies in CD-1 mice revealed a reasonable high initial brain uptake for both radiotracers, followed by a fast clearance.

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Synthesis and biological evaluation of some novel pyrazolopyrimidines incorporating a benzothiazole ring system

Acta Pharmaceutica ◽

10.2478/acph-2013-0001 ◽

2013 ◽

Vol 63 (1) ◽

pp. 19-30 ◽

Cited By ~ 11

Author(s):

Mohammed Afzal Azam ◽

Loganathan Dharanya ◽

Charu Chandrakant Mehta ◽

Sumit Sachdeva

Keyword(s):

Antimicrobial Activity ◽

Diclofenac Sodium ◽

Biological Evaluation ◽

Ring System ◽

Standard Drug ◽

Anti Inflammatory ◽

Pyrimidine Moiety ◽

Synthesis And Biological Evaluation

In the present study, a series of benzothiazol derivatives 3a-l containing pyrazolo[3,4-d]pyrimidine moiety at the second position were synthesized and characterized by analytical and spectral data. The compounds were tested for their in vitro antimicrobial activity. Compounds 1-(1,3-benzothiazol-2- yl)-3-methyl-4-phenyl-1H-pyrazolo[3,4-d]pyrimidine (3a), 1- (1,3-benzothiazol-2-yl)-4-(4-chlorophenyl)-3-methyl-1H-pyrazolo[ 3,4-d]pyrimidine (3d) and 1-(1,3-benzothiazol-2-yl)- 3-methyl-4-substituted phenyl-1H-pyrazolo[3,4-d]pyrimidines (3h-j) showed significant inhibitory activity against P. aeruginosa whereas compounds 1-(1,3-benzothiazol-2-yl)-4- (2-chlorophenyl)-3-methyl-1H-pyrazolo[3,4-d]pyrimidine (3b), 2-[1-(1,3-benzothiazol-2-yl)-3-methyl-1H-pyrazolo[3,4-d]pyrimidin- 4-yl]phenol (3e), 1-(1,3-benzothiazol-2-yl)-4-(3,4-dimethoxyphenyl)- 3-methyl-1H-pyrazolo[3,4-d]pyrimidine (3h), 4-[1-(1,3-benzothiazol-2-yl)-3-methyl-1H-pyrazolo[3,4-d]pyri midin-4-yl]-N,N-dimethylaniline (3j) and 1-(1,3-benzothiazol- 2-yl)-3-methyl-4-[2-phenylvinyl]-1H-pyrazolo[3,4-d]pyrimidine (3k) were found to be active against C. albicans. Some of these synthesized compounds were evaluated for their in vivo acute toxicity, analgesic, anti-inflammatory, and ulcerogenic actions. The tested compound 4-[1-(1,3-benzothiazol- 2-yl)-3-methyl-1H-pyrazolo[3,4-d]pyrimidin-4-yl]-N, N-dimethylaniline (3j) exhibited maximum analgesic and anti-inflammatory activities. Compounds 1-(1,3-benzothiazol- -2-yl)-3-methyl-4-(3-nitrophenyl)-1H-pyrazolo[3,4-d]pyrimidine (3i) and 3j showed a significant gastrointestinal protection compared to the standard drug diclofenac sodium.

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Synthesis, characterization and in vitro and in vivo anticancer activity of Pt(iv) derivatives of [Pt(1S,2S-DACH)(5,6-dimethyl-1,10-phenanthroline)]

Dalton Transactions ◽

10.1039/c7dt01054k ◽

2017 ◽

Vol 46 (21) ◽

pp. 7005-7019 ◽

Cited By ~ 25

Author(s):

Benjamin W. J. Harper ◽

Emanuele Petruzzella ◽

Roman Sirota ◽

Fernanda Fabiola Faccioli ◽

Janice R. Aldrich-Wright ◽

...

Keyword(s):

Anticancer Activity ◽

Biological Evaluation ◽

Synthesis And Biological Evaluation ◽

Derivatives Of

Synthesis and biological evaluation in vitro and in vivo of functionalized Pt(iv) derivatives of Pt56MeSS.

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A Cu(ii) complex targeting the translocator protein: in vitro and in vivo antitumor potential and mechanistic insights

Chemical Communications ◽

10.1039/c6cc08100b ◽

2017 ◽

Vol 53 (1) ◽

pp. 134-137 ◽

Cited By ~ 10

Author(s):

D. Montagner ◽

B. Fresch ◽

K. Browne ◽

V. Gandin ◽

A. Erxleben

Keyword(s):

Tumor Model ◽

Translocator Protein ◽

Tumor Mass ◽

Cu Complex ◽

Murine Tumor ◽

Murine Tumor Model ◽

Antitumor Potential

A Cu complex targeting the translocator protein induces a 98% reduction of tumor mass in a murine tumor model.

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Multifunctional Cyanine-Based Theranostic Probe for Cancer Imaging and Therapy

International Journal of Molecular Sciences ◽

10.3390/ijms222212214 ◽

2021 ◽

Vol 22 (22) ◽

pp. 12214

Author(s):

Cheng-Liang Peng ◽

Ying-Hsia Shih ◽

Ping-Fang Chiang ◽

Chun-Tang Chen ◽

Ming-Cheng Chang

Keyword(s):

Photothermal Therapy ◽

Radionuclide Therapy ◽

Nuclear Imaging ◽

Biological Evaluation ◽

Targeted Radionuclide Therapy ◽

Nir Fluorescence ◽

Tumor Accumulation ◽

Selective Accumulation

Cancer is one of the leading causes of death in the world. A cancer-targeted multifunctional probe labeled with the radionuclide has been developed to provide multi-modalities for NIR fluorescence and nuclear imaging (PET, SPECT), for photothermal therapy (PTT), and targeted radionuclide therapy of cancer. In this study, synthesis, characterization, in vitro, and in vivo biological evaluation of the cyanine-based probe (DOTA-NIR790) were demonstrated. The use of cyanine dyes for the selective accumulation of cancer cells were used to achieve the characteristics of tumor markers. Therefore, all kinds of organ tumors can be targeted for diagnosis and treatment. The DOTA-NIR790 labeled with lutetium-111 could detect original or metastatic tumors by using SPECT imaging and quantify tumor accumulation. The β-emission of 177Lu-DOTA-NIR790 can be used for targeted radionuclide therapy of tumors. The DOTA-NIR790 enabled imaging by NIR fluorescence and by nuclear imaging (SPECT) to monitor in real-time the tumor accumulation and the situation of cancer therapy, and to guide the surgery or the photothermal therapy of the tumor. The radionuclide-labeled heptamethine cyanine based probe (DOTA-NIR790) offers multifunctional modalities for imaging and therapies of cancer.

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