Tag: 200-300

Microwave-assisted hydrogen peroxide-mediated synthesis of benzoxazoles and related heterocycles via cyclodesulfurization was written by Kadagathur, Manasa;Sigalapalli, Dilep Kumar;Patra, Sandip;Tangellamudi, Neelima D.. And the article was included in Synthetic Communications in 2021.Quality Control of N-Phenylbenzo[d]thiazol-2-amine This article mentions the following:

A novel approach has been developed to construct benzoxazoles and similar N- and S-containing heterocycles from their corresponding isothiocyanates and o-substituted anilines via cyclodesulfurization. The reaction was found to proceed via in situ formation of disubstituted thiourea, followed by intramol. cyclodesulfurization to yield the desired benzazole. Cyclodesulfurization was achieved by the application of safer and inexpensive oxidant, hydrogen peroxide (H₂O₂) under microwave irradiation In addition to the safe environmental footprints that hydrogen peroxide exhibits, the absence of any base or additive makes it a mild and green synthetic strategy. This method contributes to the field of metal- and base-free cyclodesulfurization, thereby aids the synthesis of pharmacol. potent heterocyclic scaffolds. In the experiment, the researchers used many compounds, for example, N-Phenylbenzo[d]thiazol-2-amine (cas: 1843-21-6Quality Control of N-Phenylbenzo[d]thiazol-2-amine).

N-Phenylbenzo[d]thiazol-2-amine (cas: 1843-21-6) belongs to thiazole derivatives. The thiazole ring has been identified as a central feature of numerous natural products, perhaps the most famous example of which is epothilone. Electrophilic attack at nitrogen depends on the presence of electron density at nitrogen as well as the position and nature of substituent linked to the thiazole ring.Quality Control of N-Phenylbenzo[d]thiazol-2-amine

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Esters of sulfonic acids. VI. Preparation and reactions of alkylisothiourea p-toluenesulfonates was written by Klamann, D.;Drahowzal, F.. And the article was included in Monatshefte fuer Chemie in 1952.Reference of 1843-21-6 This article mentions the following:

ROC₈H₁₇ (R = p-MeC₆H₄SO₂) (28.4 g.), refluxed 1 hr. with 7.6 g. thiourea in 80 cc. absolute alc., cooled to -20°, filtered, the mother liquor concentrated, the product crystalline and filtered, and the remaining solution treated with ether, gave a total of 98% practically pure octylpseudothiourea p-toluenesulfonate (I), m. 112-13°. When the alkylpseudothiourea salt (II) is not to be isolated, 96% alc. may be used; the alc. is distilled, and the residue heated to dryness (steam bath). ROMe (46.5 g.) and 19 g. thiourea in 20 cc. water, heated gently with stirring until the mixture was homogeneous, then heated to dryness, gave 99% Me derivative (III), m. 144-5°. The following II were prepared, [% yield of purified product and m.p. (from absolute alc. unless specified), given]: III, 93, 144-5°; Et (IV), 90, 125-6°; Bu, 87, 166°; iso-Bu, 88, 156-7°; hexyl, 87, 139.5-40.5° (from H₂O); I, 85, 112.5-13.5° (from (C₆H₆); dodecyl (1.5-hr. reaction time), 88, 102-3° (from C₆H₆); octadecyl (1.5-hr. reaction time), 88, 103.4-4.5°; PhCH₂, 80, 181.5-2.5°; cyclohexyl, 51, 169° (decomposition); 1,2-ethanedi (V) (0.5-hr. reaction time), 84, 269-79° (decomposition) (from H₂O); 1,6-hexanedi (VI), 84, 236-6.5° (from H₂O); ClCH₂CH₂, 34 (40% V.HCl as by-product), m. 141.5-2.5° (reaction time 15 min., 50% yield with 8% V). ROCH₂CH₂Cl with PhOH gives a trace of (CH₂OPh)₂, with PhSH 55% (CH₂SPh)₂. Thiourea and ROPh or the p-NO₂ derivative (0.1 mol. each), heated 6 hrs. in 100 cc. absolute alc. gave 97-8% recovery of ROPh. To stirred 38 g. RCl and 26 cc. EtOH was added (30 min., 12-17°) 32 cc. 25% NaOH and the mixture stirred 2 hrs. at 15-18°, neutralized with HCl, treated with 13 g. thiourea and warmed 1 hr. on a water bath, concentrated to dryness, and extracted with absolute alc., giving 83% IV, m. 125-6°. To 0.2 mol. III in 300 cc. H₂O, stirred at -2 to 3°, was added Cl, the solution turning green; after 100 min. the liquid product was extracted with ether, washed with 5% NaHSO₃ and H₂O, dried, concentrated, and distilled giving 75% MeSO₂Cl, b₉ 46-7°, n_D²⁰ 1.4505, 98.34% pure (Drahowzal and Klamann, C.A. 45, 10134d). Similarly the following sulfonyl chlorides were prepared (solid products were filtered, washed, dried, taken up in ether, filtered, and recrystallized), (% yield, b₉, and n_D²⁰ or m.p., and purity, resp., given): Et, 87, 55-5.5°, 1.4539, 98.51; Bu, 85, 80-1°, 1.4559, 98.64; hexyl, 85, 106.5-7°, 1.4585, 99.94; dodecyl, 87, m. 42-3°, 98.19; PhCH₂, 88, m. 91-2°, 97.23: 1,6-hexanedi, 80, m. 82-3°, 98.80; ClCH₂CH₂, 75, 81-2°, 1.4925, – (EtSO₂Br, 58, 73-4°, -, 95.31; EtSO₂NH₂, m. 59-60°). VI (23.2 g.) refluxed 2 hrs. with 9 g. KOH in 100 cc. H₂O, cooled, diluted with H₂O, acidified with dilute H₂SO₄, extracted with ether, and the extract washed, dried, concentrated, and distilled, gave 5.6 g. HS(CH₂)₆SH, b₁₂ 105.5-6°, n_D²⁰ 1.5106. Similarly the following mercaptans were prepared: 78% Et, b₇₅₄ 34.5°; 84% Bu, b₇₅₂ 97-8°; 86% octyl, b₂₀ 88.5°, n_D²⁰ 1.4541; and 24% cyclohexyl. In the experiment, the researchers used many compounds, for example, N-Phenylbenzo[d]thiazol-2-amine (cas: 1843-21-6Reference of 1843-21-6).

N-Phenylbenzo[d]thiazol-2-amine (cas: 1843-21-6) belongs to thiazole derivatives. Thiazoles frequently appear in peptide studies. Thiazoles can also be used as protected formyl groups, which can be released in later stages of complex natural product synthesis. Thiazole is a versatile building block for the construction and lead generation of new drug discoveries. Numerous diazole-based compounds are in clinical use as anticancer, antileukemic, antiinflammatory, antiviral, antifungal, antirheumatic, immunomodulator, and antiparasitic agents.Reference of 1843-21-6

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Acylation of 2-aminobenzothiazole and its 2- and 3-derivatives was written by Rozhkova, N. K.;Saprykina, V. A.. And the article was included in Uzbekskii Khimicheskii Zhurnal in 1975.Recommanded Product: 1843-21-6 This article mentions the following:

Pyrimidobenzothiazole I was obtained in 85% yield by acylation of II (R = R1 = H) with CH2:CHCOCl in dry Me2CO at room temperature II (R = Me, Ph, H, R1 = COCH:CH2, CO2Me, CO2Et) were obtained in 48-92% yields by acylation of II (R = Me, Ph, R1 = H) with R1COCl. Analogously obtained were 90-4% III (R = Me, Ph, R1 = COCH:CH2, CO2Me, CO2Et) by acylation of III (R1 = H) with R1COCl. In the experiment, the researchers used many compounds, for example, N-Phenylbenzo[d]thiazol-2-amine (cas: 1843-21-6Recommanded Product: 1843-21-6).

N-Phenylbenzo[d]thiazol-2-amine (cas: 1843-21-6) belongs to thiazole derivatives. Thiazole rings are planar and aromatic. Thiazoles are characterized by larger pi-electron delocalization than the corresponding oxazoles and have therefore greater aromaticity. There are numerous natural products that possess a thiazole ring with broad pharmacological activities. Thiamine, also known as vitamin B1, possesses a thiazole ring linked with 2-methylpyrimidine-4-amine as hydrochloride salt.Recommanded Product: 1843-21-6

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Design, synthesis, and evaluation of 2-substituted ethenesulfonic acid ester derivatives as protein tyrosine phosphatase 1B inhibitors was written by Liu, Jingbao;Jiang, Faqin;Jin, Yan;Zhang, Yong;Liu, Jingjing;Liu, Wenlu;Fu, Lei. And the article was included in European Journal of Medicinal Chemistry in 2012.Computed Properties of C15H12N2S This article mentions the following:

Thirty-two substituted ethenesulfonic acid ester derivatives were designed, synthesized and evaluated for their inhibitory activity against protein tyrosine phosphatase 1B (PTP1B) and selectivity over T-Cell protein tyrosine phosphatase (TCPTP). A preliminary structure-activity relationship studies demonstrated that the substitution at the aromatic center and the length of linker between the hydrophobic tail and aromatic center markedly affected the inhibitory activity against PTP1B and the selectivity over TCPTP. Specifically, two compounds revealed excellent inhibitory activity to PTP1B with IC₅₀ = 1.3 μM and 1.5 μM, resp. and marked 10-fold and 20-fold selectivity over TCPTP. Cytotoxicity data showed low cytotoxicity for COS-7 cell with IC₅₀ values >100 μM for most synthesized chems. The title compounds thus formed included (1E)-2-[4-[2-(5-methyl-2-phenyl-4-oxazolyl)ethoxy]phenyl]ethenesulfonic acid Et ester (I) and related substances, such as isoxazole derivatives and thiazole derivatives The synthesis of the target compounds was achieved using 4-bromo-3-oxopentanoic acid Me ester, 4-bromo-3-oxobutanoic acid Me ester, benzamide and benzenecarbothioamide as simple starting materials. In the experiment, the researchers used many compounds, for example, 4,5-Diphenylthiazol-2-amine (cas: 6318-74-7Computed Properties of C15H12N2S).

4,5-Diphenylthiazol-2-amine (cas: 6318-74-7) belongs to thiazole derivatives. Thiazoles frequently appear in peptide studies. Thiazoles can also be used as protected formyl groups, which can be released in later stages of complex natural product synthesis. The pyridine-type nitrogen in the thiazole ring deactivates the ring for electrophilic substitution reactions, which is further reduced in acid due to protonation of the thiazole ring.Computed Properties of C15H12N2S

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Reaction of ketones with iodine and thiourea was written by King, L. Carroll;Hlavacek, Robert J.. And the article was included in Journal of the American Chemical Society in 1950.Name: 4,5-Diphenylthiazol-2-amine This article mentions the following:

The ketone (0.1 mol.), 0.2 mol. CS(NH₂)₂, and 0.1 mol. iodine, heated overnight on the steam bath, give the substituted 2-aminothiazole; the cooled reaction product is extracted with ether, the residue in boiling H₂O filtered, the filtrate made alk. with concentrated NH₄OH, and the precipitate crystallized from aqueous EtOH; if the product is an oil, it is crystallized from Skellysolve C. The m.ps. of the Ac derivatives are given in parentheses. 4-Substituted 2-aminothiazoles: p-chlorophenyl, m. 163-4°, 89% [254-5°]; p-bromophenyl, m. 180-1°, 93% [277-8°]; p-iodophenyl, m. 176-7°, 97% [302-3°]; p-methoxyphenyl, m. 204-5°, 72% [287-8°]; p-(methylmercapto)phenyl, m. 180-2°, 67% [232-3°]; p-aminophenyl, m. 174-5°, 63% [di-Ac derivative, m. 284-6°]; p-biphenylyl, m. 207-8°, 99% [252-3°]; p-tolyl, m. 124-5°, 84% [204-5°]; m-isomer, m. 79-92°, 64% [211-12°]; o-isomer, m. 81-2°, 70% [143-4°]; p-nitrophenyl, m. 285-6°, 99% [306-7°]; m-isomer, m. 188-90°, 84% [312-14°]; 2-naphthyl, m. 153-4°, 99% [239-40°]; 2-phenanthryl, m. 243-4°, 87% [304-5°]; 2-thienyl, m. 127-30°, 91% [199-207°]; tert-Bu, m. 98-9°, 71% [173-4°]; ο-hydroxyphenyl, m. 139-40°, 37% [di-Ac derivative, m. 200-3°; HI salt, m. 220-3° (each HI salt has 1 mol. H₂O)]; m-isomer, m. 136-8°, 59% [di-Ac derivative, 186-7°; HI salt, 95-7°]; p-isomer, m. 198-200°, 62% [di-Ac derivative, m. 235-7°; HI salt m. 240-2°]; 4-phenyl-5-Et, m. 68-9°, 65% [175-6°]; 4-phenyl-5-Bu, m. 103-4°, 54% [135-6°]; 4-phenyl-5-Bu, m. 60-1°, 43% [187-8°]; 4-benzyl-5-Ph, m. 139-40°, 83% [164-5°]; 4,5-di-Ph, m. 184-5°, 99% [208-9°]; 4-phenyl-5-benzoyl, m. 215-16°, 18% [237-8°]. The aminothiazole from 4-methylcyclohexanone, C₈H₁₂N₂S, m. 98-9°, 66% [162-3°]; the 3-isomer gives 24% 2-amino-5(or -7)-methyl-4,5,6,7 -tetrahydrobenzothiazole, m. 110-11° [150-1°]. Compound from cycloheptanone, C₈H₁₂N₂S, m. 75-6° 60% [124-5°]; from hydrindone, C₁₀H₈N₂S, m. 213-14°, 53% [284-5°]; from 3,4-dihydro-1(2H)-naphthalenone, m. 133-4°, 52% [233-4°]; acenaphthenone gives 99% 8-aminoacenaphtho-1,2-thiazole, bright red, m. 205-7° [309-11°]. Bromoacetomesitylene (4.6 g.) yields 3.8 g. 2,4,6-trimethylphenacylisothiuronium bromide, m. 280-2°; it could not be cyclized to a thiazole. In the experiment, the researchers used many compounds, for example, 4,5-Diphenylthiazol-2-amine (cas: 6318-74-7Name: 4,5-Diphenylthiazol-2-amine).

4,5-Diphenylthiazol-2-amine (cas: 6318-74-7) belongs to thiazole derivatives. Thiazoles frequently appear in peptide studies. Thiazoles can also be used as protected formyl groups, which can be released in later stages of complex natural product synthesis. Thiazole sulfonation occurs only under forcing conditions: the action of oleum at 250 °C for 3 hours in the presence of mercury(II) sulfate leads to 65% formation of 5-thiazole sulfonic acid.Name: 4,5-Diphenylthiazol-2-amine

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Oxidative coupling of formamides with β-dicarbonyl compounds and the synthesis of 2-aminobenzothiazole using Cu(II)-functionalized Fe₃O₄ nanoparticles was written by Azizi, Kobra;Karimi, Meghdad;Heydari, Akbar. And the article was included in Tetrahedron Letters in 2015.Application of 1843-21-6 This article mentions the following:

The Fe₃O₄@EDTA-Cu(II) nanoparticles catalyzed oxidative coupling of formamides with β-dicarbonyl compounds is developed using tert-Bu hydroperoxide as an oxidant. In general, the enol carbamates are synthesized in excellent yields (up to 92%) under the optimized reaction conditions. Fe₃O₄@EDTA-Cu(II) has the advantage of being magnetically recoverable. Also, we have established a highly efficient Fe₃O₄@EDTA-Cu(II)-catalyzed tandem reaction of 2-iodoanilines with isothiocyanates for the synthesis of 2-aminobenzothiazoles. In the experiment, the researchers used many compounds, for example, N-Phenylbenzo[d]thiazol-2-amine (cas: 1843-21-6Application of 1843-21-6).

N-Phenylbenzo[d]thiazol-2-amine (cas: 1843-21-6) belongs to thiazole derivatives. The thiazole ring is notable as a component of the vitamin thiamine (B1). The pyridine-type nitrogen in the thiazole ring deactivates the ring for electrophilic substitution reactions, which is further reduced in acid due to protonation of the thiazole ring.Application of 1843-21-6

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Thiazole derivatives as vulcanization accelerators. I. Reaction of carbon disulfide, sulfur, and thiocarbanilide was written by Kimijima, Takuzo;Miyama, Shunichi. And the article was included in Kogyo Kagaku Zasshi in 1942.COA of Formula: C13H10N2S This article mentions the following:

A mixture of 231 g. thiocarbanilide, 67.5 g. S, and 83.6 g. CS₂ was heated in an autoclave at 180-260° for 6 hrs. to obtain mercaptobenzothiazole. The best temperature was 220°, at which the yield was 88%. At lower temperatures, anilidobenzothiazole was the chief product. The same was true when the mixture was heated at higher temperatures for a short time. When the reaction temperature was too high, benzothiazole was formed at the expense of mercaptobenzothiazole. In the experiment, the researchers used many compounds, for example, N-Phenylbenzo[d]thiazol-2-amine (cas: 1843-21-6COA of Formula: C13H10N2S).

N-Phenylbenzo[d]thiazol-2-amine (cas: 1843-21-6) belongs to thiazole derivatives. Thiazoles are a class of five-membered rings containing nitrogen and sulfur with excellent antitumor, antiviral and antibiotic activities. Thiazole sulfonation occurs only under forcing conditions: the action of oleum at 250 °C for 3 hours in the presence of mercury(II) sulfate leads to 65% formation of 5-thiazole sulfonic acid.COA of Formula: C13H10N2S

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Potassium iodide and ammonium nitrate catalyzed aerobic oxidative cyclization of ketones with thioureas in ionic liquid: an access to 2-aminothiazoles was written by Zhao, Jinwu;Xu, Jingxiu;Chen, Jiaxi;He, Minghua;Wang, Xiaoqin. And the article was included in Tetrahedron in 2015.Formula: C15H12N2S This article mentions the following:

An efficient procedure for the synthesis of 2-aminothiazoles via KI/NH₄NO₃-catalyzed oxidative cyclization of ketones and thioureas using mol. oxygen as a green oxidant is reported. Different ketones and thioureas went through the transformation and gave corresponding 2-aminothiazole heterocycles in satisfactory yields. E.g., in presence of KI/NH₄NO₃, H₂SO₄, and mol. oxygen in [Bmim]OTf/H₂O (4:1), oxidative cyclization of PhCOMe and H₂NCSNH₂ gave 95% 2-aminothiazole derivative (I). In the experiment, the researchers used many compounds, for example, 4,5-Diphenylthiazol-2-amine (cas: 6318-74-7Formula: C15H12N2S).

4,5-Diphenylthiazol-2-amine (cas: 6318-74-7) belongs to thiazole derivatives. The higher aromaticity of thiazole is due to delocalization of a lone pair of sulfur electrons across the ring, which is evidenced by chemical shifts of ring hydrogen at δ 7.27 and 8.77 ppm (C2 and C4), indicating diamagnetic ring current.Various laboratory methods exist for the organic synthesis of thiazoles. For example, 2,4-dimethylthiazole is synthesized from thioacetamide and chloroacetone.Formula: C15H12N2S

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Synthesis of styryl dyes: Part I – Condensation of 2-substituted N-phenacylthiazolium bromides with p-N,N-dimethylaminobenzaldehyde was written by Sharma, A.;Sarangi, B. K.;Behera, Rajani K.. And the article was included in Indian Journal of Chemistry in 1985.Recommanded Product: 4,5-Diphenylthiazol-2-amine This article mentions the following:

The phenacylthiazolium bromides I (R = H, Cl, O₂N; R¹ = Ph, β-naphthyl, R² = H; R¹ = R² = Ph; R¹R² = benzo), prepared from the corresponding 2-amino-4-phenylthiazole and phenacyl bromide, were condensed with p-Me₂NC₆H₄CHO to give the imidazothiazolium bromides II. In the experiment, the researchers used many compounds, for example, 4,5-Diphenylthiazol-2-amine (cas: 6318-74-7Recommanded Product: 4,5-Diphenylthiazol-2-amine).

4,5-Diphenylthiazol-2-amine (cas: 6318-74-7) belongs to thiazole derivatives. Thiazole rings are planar and aromatic. Thiazoles are characterized by larger pi-electron delocalization than the corresponding oxazoles and have therefore greater aromaticity. Electrophilic attack at nitrogen depends on the presence of electron density at nitrogen as well as the position and nature of substituent linked to the thiazole ring.Recommanded Product: 4,5-Diphenylthiazol-2-amine

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Radical C-H ¹⁸F-difluoromethylation of heteroarenes with [¹⁸F]difluoromethyl heteroaryl-sulfones by visible light photoredox catalysis was written by Lemos, Agostinho Luis Pereira;Trump, Laura;Lallemand, Benedicte;Pasau, Patrick;Mercier, Joel;Lemaire, Christian;Monbaliu, Jean-Christophe;Genicot, Christophe;Luxen, Andre. And the article was included in Catalysts in 2020.Electric Literature of C7H4N2O2S2 This article mentions the following:

Six new [¹⁸F]difluoromethyl heteroaryl-sulfones ArSO₂CF[¹⁸F] [Ar = 5-methoxybenzothiazol-2-yl, N-methylbenzimidazol-2-yl, 1-phenyltetrazol-5-yl, etc.] were prepared and, based on overall radiochem. yields (RCYs), three of these reagents ArSO₂CF[¹⁸F] [6-methoxy-1,3-benzothiazol-2-yl, 6-nitro-1,3-benzothiazol-2-yl, 1-phenyltetrazol-5-yl] were selected for fully automated radiosynthesis on a FASTlab synthesizer (GE Healthcare) at high level of starting radioactivity. Subsequently, their efficiency as ¹⁸F-difluoromethylating reagents was evaluated using antiherpetic drug acyclovir as a model substrate. The results showed that introduction of mol. modifications in structure of previously reported ArSO₂CF[¹⁸F] [Ar = benzothiazol-2-yl] influenced amount of fac-Ir^III(ppy)₃ and residence time needed to ensure a complete C-H ¹⁸F-difluoromethylation process. The photocatalytic C-H ¹⁸F-difluoromethylation reaction with selected reagents was extended to other heteroarenes. Radical-trapping experiments demonstrated likely involvement of radical species in C-H ¹⁸F-difluoromethylation process. In the experiment, the researchers used many compounds, for example, 5-Nitrobenzothiazole-2-thiol (cas: 58759-63-0Electric Literature of C7H4N2O2S2).

5-Nitrobenzothiazole-2-thiol (cas: 58759-63-0) belongs to thiazole derivatives. Thiazole rings are planar and aromatic. Thiazoles are characterized by larger pi-electron delocalization than the corresponding oxazoles and have therefore greater aromaticity. Thiazole sulfonation occurs only under forcing conditions: the action of oleum at 250 °C for 3 hours in the presence of mercury(II) sulfate leads to 65% formation of 5-thiazole sulfonic acid.Electric Literature of C7H4N2O2S2

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica