93186-69-7Relevant academic research and scientific papers
Environment-friendly and efficient synthesis of 2-aminobenzo-xazoles and 2-aminobenzothiazoles catalyzed by: Vitreoscilla hemoglobin incorporating a cobalt porphyrin cofactor
Li, Fengxi,Li, Zhengqiang,Su, Jiali,Wang, Chunyu,Wang, Ciduo,Wang, Lei,Xu, Yaning,Zhao, Nan
, p. 8047 - 8052 (2021/11/01)
In this study, an environment-friendly and efficient artificial Vitreoscilla hemoglobin (VHb) for the synthesis of 2-aminobenzoxazoles and 2-aminobenzothiazoles has been reported. We demonstrate an expression-based porphyrin substitution strategy to produce VHb containing cobalt porphyrin instead of native hemin, which can catalyze the oxidative cyclization of corresponding 2-aminobenzoxazoles and 2-aminobenthiazoles with up to 97% yield and 4850 catalytic turnovers in water under aerobic conditions. Hence, we provide a green and mild method for the synthesis of 2-aminobenzoxazoles and 2-aminobenzothiazoles. In addition, we indicate the value of porphyrin ligand substitution as a strategy to tune and enhance the catalytic properties of hemoproteins in non-natural reactions.
Electrochemical NaI/NaCl-mediated one-pot synthesis of 2-aminobenzoxazoles in aqueous mediaviatandem addition-cyclization
Huynh, Thao Nguyen Thanh,Koguchi, Shinichi,Rerkrachaneekorn, Tanawat,Sukwattanasinitt, Mongkol,Tankam, Theeranon,Wacharasindhu, Sumrit
supporting information, p. 5189 - 5194 (2021/07/29)
An electrochemical synthesis of 2-aminobenzoxazoles from 2-aminophenols and isothiocyanates was successfully developed in a one-pot fashion. Using inexpensive and widely available NaI and NaCl co-operatively in catalytic amounts, our electrosynthesis approach provided various 2-aminobenzoxazole products in moderate to high yields in an open-flask type undivided cell without using any external supporting electrolyte and base. The protocol can be applied to the synthesis of 2-aminobenzothiazoles from the corresponding 2-thiophenols in moderate yields. This protocol has many benefits. It is metal-free and highly scalable and uses inexpensive mediators and EtOH/water as an environmentally friendly solvent under mild conditions.
Iodide catalyzed synthesis of 2-aminobenzoxazoles via oxidative cyclodesulfurization of phenolic thioureas with hydrogen peroxide
Yadav, Vinod K.,Srivastava, Vishnu P.,Yadav, Lal Dhar S.
, p. 252 - 255 (2017/12/26)
A convenient and efficient oxidative cyclodesulfurization of o-phenolic thioureas to 2-aminobenzoxazoles employing TBAI (tetrabutylammonium iodide)/H2O2 catalyst/reagent system is reported. The protocol utilizes and offers a number o
One-pot reaction for the synthesis of N-substituted 2-aminobenzoxazoles using triphenylbismuth dichloride as cyclodesulfurization reagent
Murata, Yuki,Matsumoto, Natsuho,Miyata, Maya,Kitamura, Yuki,Kakusawa, Naoki,Matsumura, Mio,Yasuike, Shuji
, p. 18 - 23 (2018/02/09)
The treatment of various 2-aminophenols with isothiocyanates afforded thioureas, which were reacted in situ with triphenylbismuth dichloride in the presence of triethylamine to give the expected N-substituted benzoxazol-2-amines in good to excellent yields. Triphenylbismuth dichloride promoted the successful cyclodesulfurization of thioureas with short reaction times under mild reaction conditions. This reaction is the first example of the synthesis of heterocyclic rings using a pentavalent organobismuth reagent.
A new NBS/oxone promoted one pot cascade synthesis of 2-aminobenzimidazoles/2-aminobenzoxazoles: A facile approach
Daswani, Ujla,Dubey, Nitin,Sharma, Pratibha,Kumar, Ashok
supporting information, p. 8093 - 8099 (2016/09/12)
A new strategy for the synthesis of 2-aminobenzimidazoles via a reaction of α-halogenated cyclohexanone with guanidine is reported. It provides a facile N-bromosuccinimide (NBS) mediated transition metal free, sustainable path for the synthesis of 2-substituted azoles. NBS along with the oxone promotes in situ halogenation of cyclohexanone, which in turn, when allowed to react with guanidine, afforded 2-aminobenzimidazoles (2-ABI). This eco-friendly protocol provides a competent laboratory synthesis method associated with significant advantages such as greater selectivity, cost-efficiency, mild reaction conditions, absence of chromatographic purification, clean reaction profile, and a simple work-up procedure to furnish high yields. The structures of all the synthesized compounds were confirmed on the basis of IR, 1H and 13C NMR, mass spectrometry, and elemental analyses data. In addition, we have also extended the scope of this strategy for obtaining 2-amino substituted benzoxazoles.
Visible-light-promoted cyclodesulfurization of phenolic thioureas: An organophotoredox catalytic approach to 2-aminobenzoxazoles
Yadav, Vinod K.,Srivastava, Vishnu P.,Yadav, Lal Dhar S.
, p. 155 - 158 (2015/12/24)
A facile and efficient one-pot operation for the photo-oxidative cyclodesulfurization of o-phenolic thioureas to afford 2-aminobenzoxazoles is reported. The protocol could be executed under visible light irradiation employing eosin Y as an organophotoredo
Straightforward synthesis of 2-anilinobenzoxazoles and -benzothiazoles via mechanochemical ball-milling-promoted one-pot reactions
Zhang, Ze,Wang, Fang-Jian,Wu, Hao-Hao,Tan, Ya-Jun
supporting information, p. 440 - 441 (2015/05/27)
Under mechanochemical ball-milling and solvent-free conditions, a series of 2-anilinobenzoxazoles and -thiazoles were synthesized directly from the one-pot reaction of anilines, CS2, and 2-aminophenol and -thiophenol. This protocol exhibits the
Highly efficient one-pot synthesis of 2-aminobenzoxazoles using triflic acid as a cyclodesulfurizing reagent
Khatik, Gopal L.,Dube, Namita,Pal, Anang,Nair, Vipin A.
experimental part, p. 2631 - 2639 (2011/08/07)
An efficient one-pot synthetic strategy for 2-aminobenzoxazoles was developed from isothiocyanates and 2-aminophenol using triflic acid as a cyclodesulfurizing reagent. Taylor & Francis Group, LLC.
One-pot synthesis of five and six membered N, O, S-heterocycles using a ditribromide reagent
Yella, Ramesh,Patel, Bhisma K.
experimental part, p. 754 - 763 (2010/11/03)
In a one-pot procedure, bromine less brominating reagent 1,1′-(ethane-1,2-diyl)dipyridinium bistribromide (EDPBT) has been utilized as an efficient desulfurizing agent for the construction of a library of heterocycles containing N, O, and S starting from aryl/alkyl isothiocyanates. In this approach, aryl/alkyl isothiocyanate reacts with o-phenylenediamine (o-PD), o-aminophenol, and o-aminothiophenol to form their monothiourea which on desulfurization with EDPBT led to the formation of corresponding 2-aminobenzimidazoles, 2-aminobenzoxazoles, and 2-aminobenzothiazoles, respectively. An interesting regioselectivity was observed for unsymmetrical thiourea having a naphthyl moiety on the one side and an ortho amino or an ortho hydroxy phenyl group on the other side giving a completely different product which is mainly dependent on the nature of the nucleophiles (-OH or -NH 2). Further, the bis-thioureas resulted from the aliphatic 1,2-diamine with 2 equiv of aryl isothiocyanates on treatment with EDPBT gave imidazolidenecarbothioamides, whereas bis-thioureas resulted from aromatic 1,2-diamine yielded benzimidazoles with concurrent expulsion of an isothiocyanate unit. This method is simple and applied to various substrates which are amenable to bromination that reveals the desulfurizing ability of EDPBT predominating over its brominating ability. Finally, the spent reagent EDPDB can be recovered, regenerated, and reused without any loss of activity.
Substituted 4-amino-1H-pyrazolo[3,4-d]pyrimidines as multi-targeted inhibitors of insulin-like growth factor-1 receptor (IGF1R) and members of ErbB-family receptor kinases
Wang, Gary T.,Mantei, Robert A.,Hubbard, Robert D.,Wilsbacher, Julie L.,Zhang, Qian,Tucker, Lora,Hu, Xiaoming,Kovar, Peter,Johnson, Eric F.,Osterling, Donald J.,Bouska, Jennifer,Wang, Jieyi,Davidsen, Steven K.,Bell, Randy L.,Sheppard, George S.
scheme or table, p. 6067 - 6071 (2010/11/18)
This Letter describes the lead discovery, optimization, and biological characterization of a series of substituted 4-amino-1H-pyrazolo[3,4-d] pyrimidines as potent inhibitors of IGF1R, EGFR, and ErbB2. The leading compound 11 showed an IGF1R IC50 of 12 nM, an EGFR (L858R) IC50 of 31 nM, and an ErbB2 IC50 of 11 nM, potent activity in cellular functional and anti-proliferation assays, as well as activity in an in vivo pharmacodynamic assay.
