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Synthetic Approaches to Inhibitors of Isoprenoid Biosynthesis
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2019
Pedro Merino, Loredana Maiuolo, Ignacio Delso, Vincenzo Algieri, Antonio De Nino, Tomas Tejero
Pamidronate (5), Alendronate (6), and neridronate (7) were prepared as mono- and diesters, starting from protected substrates on the amino group. Further deprotection was performed by using an excess of hydrazine in water at physiological pH (Guenin et al., 2007).
Molecular Aspects of the Activity and Inhibition of the FAD-Containing Monoamine Oxidases
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2019
The original discovery of the antidepressant effect of hydrazines came from the observation of mood elevation in tuberculosis patients treated with isoniazid. Hydrazines were then characterized as effective MAO inhibitors (Zeller et al., 1955). Both phenelzine and isocarboxazid carry the risk of liver toxicity but remain useful for treatment-resistant depression. The reversible inhibition of MAO by phenelzine is poor (Ki is 47 μM for MAO A, 15 μM for MAO B (Binda et al., 2008), as it is in rat and pig brain (Tipton and Spires, 1971). Inactivation requires that the hydrazine act first as a substrate. The normal product from the oxidation of the hydrazine is an imine that is hydrolysed to the aldehyde and released as usual with concomitant H2O2 production. Alternatively, the product could be a diazene that reacts with oxygen giving a radical that could alkylate the flavin. Inactivation of MAO A and of MAO B follows the same O2-dependent mechanism with some turnover for each inactivation event (the partition ratio). The kinetics of inactivation give kinact/Kinact equal to 18 min−1M−1 for MAO A and 3 min−1M−1 for MAO, B both with a partition ratio of turnover to inactivation of about 40 (Binda et al., 2008). The crystal structure shows that the adduct formed is at N5 of the FAD (Fig. 10.4).
Dietary Fibers And Colon Cancer*
Published in Herman Autrup, Gary M. Williams, Experimental Colon Carcinogenesis, 2019
While the carcinogenicity of these agents is not definitively known for humans, both synthetic and natural hydrazines can be found in the environment as industrial and food contaminants.40–46 1,1-Dimethylhydrazine has been detected in significant quantities in tobacco plants, although a definite relationship between colon cancer and smoking has not been established. Hydrazines also are found in some species of wild and cultivated mushrooms (i.e., Gyromitra, Helvella). Although the mechanism is unclear, these agents may be responsible for symptoms of gastrointestinal toxicity (i.e., diarrhea) following mushroom ingestion. Hydrazines are found in rocket propellants, while hydroxyethylhydrazine is used as a ripener for certain plants. Hydrazines are commercially produced for use in pesticides, herbicides, blowing agents for plastics, and treatment for water. Several hydrazines reportedly produce tumors in experimental animals. Other related hydrazine compounds cause DNA damage to human cells cultured in vitro under certain conditions. While the role of these agents in the development of human colon cancer is far from being established, their potential significance may be broader than simply being used for induction of experimental tumors in rodent species.
Discovery of novel enasidenib analogues targeting inhibition of mutant isocitrate dehydrogenase 2 as antileukaemic agents
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2023
Ahmed F. Khalil, Tarek F. El-Moselhy, Eman A. El-Bastawissy, Rasha Abdelhady, Nancy S. Younis, Mervat H. El-Hamamsy
Target compounds, of series (I), 6a–l, and series (II), 7a–l were prepared as displayed in Scheme 1. The three chlorine atoms of cyanuric chloride, 1 disclosed diverse reactivity and can be substituted gradually at different temperatures38. Compounds 3a,b were prepared from cyanuric chloride 1via nucleophilic substitution of the first chlorine atom with morpholine, 2a or piperidine, 2b at 0–5 °C to afford analogues, 3a and 3b, respectively. Compounds 3a,b underwent nucleophilic substitution of the remaining two chlorine atoms with two hydrazine groups through heating under reflux with excess amount of hydrazine hydrate to provide the trisubstituted s-triazine derivatives, 4a,b, respectively. Condensation of hydrazine derivatives, 4a,b with various aldehydes yielded the corresponding hydrazones, 6a–l and 7a–l, respectively.
Identification of 3-(piperazinylmethyl)benzofuran derivatives as novel type II CDK2 inhibitors: design, synthesis, biological evaluation, and in silico insights
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2022
Wagdy M. Eldehna, Raed M. Maklad, Hadia Almahli, Tarfah Al-Warhi, Eslam B. Elkaeed, Mohammed A. S. Abourehab, Hatem A. Abdel-Aziz, Ahmed M. El Kerdawy
The ester 6 (2 g, 5.5 mmol) was dissolved in 20 ml of absolute ethanol then (1.1 ml, 22 mmol) of hydrazine hydrate (99%) was added portionwise while stirring at ambient temperature. Then, the whole reaction mixture was heated at reflux for 4h. After that, ethanols as well as most of hydrazine hydrate were evaporated under vacuum using rotavap. The remaining residue was then washed thoroughly for several times with distilled water while vigorous stirring then decantation after each time. Finally, the residue was crystallised from hot ethanol 80% to afford the hydrazide 7 as white crystals, m.p = 243–244 °C, yield = 1.41 g, 73% of theoretical. The structure of the hydrazide 7 was further confirmed by 1H NMR. The product was used then in the next steps without further purification. 1H NMR (400-MHz, DMSO-d6) δ 10.68 (s, 1H, NH hydrazide), 7.97 (d, J = 7.8 Hz, 1H, Ar˗H at C4 of benzofuran ring), 7.66 (d, J = 8.3 Hz, 1H, Ar˗H at C7 of benzofuran ring), 7.49 (t, J = 7.6 Hz, 1H, Ar˗H at C6 of benzofuran ring), 7.37 (t, J = 7.4 Hz, 1H, Ar˗H at C5 of benzofuran ring), 7.23 (t, J = 7.5 Hz, 2H, two Ar˗H at C3,5 phenyl), 6.94 (d, J = 7.9 Hz, 2H, two Ar˗H at C2,6 phenyl), 6.80 (t, J = 7.1 Hz, 1H, one Ar˗H at C4 phenyl), 4.66 (s, 2H, NH2 hydrazide), 4.06 (s, 2H, methylene at C3 of benzofuran ring), 3.17 (s, 4H, two CH2N piprazine moiety), 2.65 (s, 4H, two CH2N piprazine moiety).
Bimetallic nickel-ferrite nanorod particles: greener synthesis using rosemary and its biomedical efficiency
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2020
Hajar Q. Alijani, Shahram Pourseyedi, Masoud Torkzadeh-Mahani, Alexander Seifalian, Mehrdad Khatami
Nejati and Zabihi [34] were synthesised NiFe2O4 bimetallic NP by the hydrothermal method using Hydrazine hydrate. Hydrazine hydrate is toxic to humans [35]. Current mentioned chemical methods usually have disadvantages such as dependence on expensive equipment, high energy consumption and dependence on chemical compounds toxic to the environment and humans [36–43]. Therefore, finding simple, economical, inexpensive, non-toxic and environmentally friendly methods are very important and necessary for the synthesis of these types of NP. A method that can eliminate the need to use any harmful chemicals is shown in [44]. The methods that recently attracted the attention of scientists are synthesis of nanostructures using natural resources such as herbal, bacterial, fungal or their derivative (green methods). Compared with chemical synthesis methods, green methods have various important advantages, including facility, low external energy consumption, affordable, rapid synthesis process, non-toxicity, convenient one-step process and eco-friendly [45–49].