622-77-5Relevant articles and documents
Inhibition of nitric oxide synthase with pyrazole-1-carboxamidine and related compounds
Southan, Garry J.,Gauld, Douglas,Lubeskie, Andrew,Zingarelli, Basilia,Cuzzocrea, Salvatore,Salzman, Andrew L.,Szabo, Csaba,Wolff, Donald J.
, p. 409 - 417 (1997)
Guanidines, amidines, S-alkylisothioureas, and other compounds containing the amidine function (-C(=NH)NH2) have been described as inhibitors of the generation of nitric oxide (NO) by NO synthase (NOS). Mere we report on the inhibition of the activity of NOS isoforms by compounds in which the amidine function is attached to a nitrogen of 1,2 diazo heterocycles to form N-carboxamidines and related compounds. 1H-Pyrazole-1-carboxamidine HCl (PCA) inhibited the activity of purified inducible NOS (iNOS), endothelial NOS (eNOS), and neuronal NOS (nNOS) isoforms to a similar extent (IC50 = 0.2 μM). 3-Methyl-PCA and 4-methyl-PCA showed reduced potencies, but a preference for iNOS [IC50 = 5 and 2.4 μM, respectively; cf. N(G)-methyl-L-arginine (NMA) IC50 = 6 μM]. Inhibition of purified iNOS by PCAs could be reversed completely by excess L arginine, while their inhibition of NO production by stimulated RAW macrophages could be reversed by transfer to a drug-free medium. This suggests a competitive mode of inhibition. PCA caused potent concentration dependent inhibition of the acetylcholine-induced, endothelium-dependene relaxations of precontracted rat thoracic aorta (IC50 = 30 μM). 4-Methyl-PCA inhibited the relaxations only at ≤300 μM. In contrast, 4-methyl-PCA was more effective than both PCA and NMA in restoring the ex vivo contractility of aortic rings taken from lipopolysaccharide-treated rats. PCA and NMA, but not 4-methyl-PCA, caused marked increases in mean arterial pressure when administered i.v. to anesthetized rats. In conclusion, PCA and related compounds caused potent inhibition of NOS. Substitution of the pyrazole ring reduced potency, but improved selectivity towards iNOS as exemplified by 4-methyl-PCA.
Iron-mediated desulphurization approach: synthesis of cyanamides and their conversions
Nannapaneni, Madhavi,Pendem, Venkata Bhavanarushi,Tamminana, Ramana
, (2022/01/12)
The iron-mediated efficient multi-component method has been demonstrated for the synthesis of substituted cyanamides from isothiocyanates under mild reaction conditions. Subsequent nucleophilic addition and desulfurization are involved in this proposed synthetic methodology. All the reactions are rapid, facile, and accomplished at room temperature. A variety of substrates readily underwent the optimized reaction conditions to provide their respective target products in good to excellent yields. Furthermore, we have confirmed that no other by-products could be identified during our experimental reaction process. Graphical abstract: Iron-mediated efficient multi-component method has been demonstrated for the synthesis of substituted cyanamides from isothiocyanates under mild reaction conditions. Subsequent nucleophilic addition and desulfurization are involved in this proposed synthetic methodology.[Figure not available: see fulltext.].
SO2F2-Mediated one-pot cascade process for transformation of aldehydes (RCHO) to cyanamides (RNHCN)
Ding, Chengrong,Ge, Shuting,Wei, Junjie,Zhang, Guofu,Zhao, Yiyong
, p. 17288 - 17292 (2020/05/18)
A simple, mild and practical cascade process for the direct conversion of aldehydes to cyanamides was developed featuring a wide substrate scope and great functional group tolerability. This method allows for transformations of readily available, inexpensive, and abundant aldehydes to highly valuable cyanamides in a pot, atom, and step-economical manner with a green nitrogen source. This protocol will serve as a robust tool for the installation of the cyanamide moiety in various complicated molecules.
A cascade process for directly converting nitriles (RCN) to cyanamides (RNHCN) via SO2F2-activated Tiemann rearrangement
Zhang, Guofu,Zhao, Yiyong,Ding, Chengrong
supporting information, p. 7684 - 7688 (2019/08/30)
A simple, mild and practical process for the direct conversion of nitriles to cyanamides was newly discovered and exhibited a wide substrate scope as well as great functional group-tolerability (36 examples). In this efficient strategy, the in situ generated amidoximes obtained from the reaction of nitriles with hydroxylamine subsequently underwent Tiemann rearrangement, producing the corresponding cyanamides with great isolated yields under SO2F2. Additionally, the control experiments reportedly shed light on the tentative mechanism involved in the formation and elimination of the key intermediate: a sulfonyl ester.
One-pot three-component tandem reaction: Synthesis of aryl/alkyl cyanamides libraries and their further conversion into tetrazole derivatives
Mandapati, Usharani,Mandapati, Pavan,Pinapati, Srinivasarao,Tamminana, Ramana,Rudraraju, Rameshraju
, p. 500 - 510 (2018/02/06)
We have developed methodology for the synthesis of aryl/alkyl cyanamides from amines in one-pot four steps reaction using cheap, readily available and air stable copper source as catalyst under mild reaction conditions. We have also studied the application of cyanamides. In this connection, we could construct aryl tetrazolamine from cyanamides using click reaction.
Cobalt-promoted one-pot reaction of isothiocyanates toward the synthesis of aryl/alkylcyanamides and substituted tetrazoles
Seelam, Mohan,Kammela, Prasada Rao,Shaikh, Bajivali,Tamminana, Ramana,Bogiri, Sujatha
, p. 535 - 544 (2018/07/05)
[Figure not available: see fulltext.] The synthesis of cyanamides and tetrazoles from isothiocyanates through tandem reaction using cobalt catalyst has been demonstrated. In the case of tetrazole preparation, the reaction involved addition/desulfurization/nucleophilic addition/electrocyclization, whereas aromatic cyanamides were constructed from isothiocyanates through addition/desulfurization. Cheap cobalt sulfate was used for the synthesis of various cyanamides and tetrazoles. In addition, cobalt catalyst was found to be desulfurization reagent that has not been previously reported. The final products have been obtained from starting precursors in good to high yield.
A novel one-pot synthesis of isothiocyanates and cyanamides from dithiocarbamate salts using environmentally benign reagent tetrapropylammonium tribromide
Kuotsu, Neivotsonuo Bernadette,Jamir, Latonglila,Phucho, Tovishe,Sinha, Upasana Bora
, p. 832 - 841 (2018/01/17)
A highly efficient and simple protocol for the synthesis of isothiocyanates and cyanamides from their respective amines in the presence of a mild, efficient, and non-toxic reagent tetrapropylammonium tribromide is described. High environmental acceptability of the reagents, cost effectiveness and high yields are the important attributes of this methodology.
One-Pot Synthesis of N-Monosubstituted Ureas from Nitriles via Tiemann Rearrangement
Wang, Chien-Hong,Hsieh, Tsung-Han,Lin, Chia-Chi,Yeh, Wen-Hsiung,Lin, Chih-An,Chien, Tun-Cheng
supporting information, p. 1823 - 1826 (2015/08/06)
Amidoximes, obtained from the reaction of nitriles with hydroxylamine, underwent Tiemann rearrangement in the presence of benzenesulfonyl chlorides (TsCl or o-NsCl) to form the N-substituted cyanamides. Subsequently, acidic hydrolysis of the cyanamides afforded the corresponding N-monosubstituted ureas. The synthesis of N-monosubstituted ureas from nitriles was accomplished by three steps in one pot, which provides a direct access to versatile N-monosubstituted urea derivatives from a wide variety of nitriles.
Synthesis, structure activity relationship, radiolabeling and preclinical evaluation of high affinity ligands for the ion channel of the N-methyl-d-aspartate receptor as potential imaging probes for positron emission tomography
Klein, Pieter J.,Christiaans, Johannes A.M.,Metaxas, Athanasios,Schuit, Robert C.,Lammertsma, Adriaan A.,Van Berckel, Bart N.M.,Windhorst, Albert D.
, p. 1189 - 1206 (2015/03/04)
The N-methyl-d-aspartate receptor (NMDAr) is involved in many neurological and psychiatric disorders including Alzheimer's disease and schizophrenia. Currently, it is not possible to assess NMDAr availability in vivo. The purpose of this study was to develop a positron emission tomography (PET) ligand for the NMDAr ion channel. A series of di- and tri-N-substituted diarylguanidines was synthesized. In addition, in vitro binding affinity for the NMDAr ion channel in rat forebrain membrane fractions was assessed. Compounds 10, 11 and 32 were radiolabeled with either carbon-11 or fluorine-18. Ligands [11C]10 and [18F]32 were evaluated ex vivo in B6C3 mice. Biodistribution studies showed higher uptake of [11C]10 and [18F]32 in forebrain regions compared with cerebellum. In addition, for [11C]10 54% and for [18F]32 70% of activity in the brain at 60 min was due to intact tracer. Pre-treatment with MK-801 (0.6 mg·kg-1, ip) slightly decreased uptake in NMDAr-specific regions for [18F]32, but not for [11C]10. As such [18F]32 has the best characteristics as a PET tracer for the ion channel of the NMDAr.
Practical synthesis of N -substituted cyanamides via tiemann rearrangement of amidoximes
Lin, Chia-Chi,Hsieh, Tsung-Han,Liao, Pen-Yuan,Liao, Zhen-Yuan,Chang, Chih-Wei,Shih, Yu-Chiao,Yeh, Wen-Hsiung,Chien, Tun-Cheng
supporting information, p. 892 - 895 (2014/03/21)
A facile and general synthesis of various N-substituted cyanamides was accomplished by the Tiemann rearrangement of amidoximes with benzenesulfonyl chlorides (TsCl or o-NsCl) and DIPEA.
