Heterocyclic Building Blocks-Thiazole

Chitosan-SO₃H: a green approach to 2-aryl/heteroaryl benzothiazoles under solvent-free conditions at room temperature was written by Bathula, Surendra Bose;Khagga, Mukkanti;Venkatasubramanian, Hariharakrishnan. And the article was included in Asian Journal of Chemistry in 2018.Synthetic Route of C14H11NS This article mentions the following:

An efficient green protocol was developed for the synthesis of 2-aryl/heteroaryl benzothiazoles by intramol. cyclocondensation of 2-mercaptoaniline with aryl/heteroaryl aldehydes using chitosan-SO₃H as an efficient biocompatible and reusable heterogenous solid acid catalyst in presence of air under solvent free conditions at room temperature In the experiment, the researchers used many compounds, for example, 2-(4-Methylphenyl)benzothiazole (cas: 16112-21-3Synthetic Route of C14H11NS).

2-(4-Methylphenyl)benzothiazole (cas: 16112-21-3) belongs to thiazole derivatives. The thiazole ring is notable as a component of the vitamin thiamine (B1). 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.Synthetic Route of C14H11NS

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

Thiomethylation and thiohydroxylation – a new pathway of metabolism of heterocyclic compounds was written by Pal, R.;Spiteller, G.. And the article was included in Xenobiotica in 1982.Reference of 20485-41-0 This article mentions the following:

Gas-liquid chromatog.-mass spectral anal. of thin-layer chromatog. fractions of urine samples from patients treated with clomethiazole (I) [533-45-9] revealed 2 minor metabolites formed by thiomethylation and thiohydroxylation, namely 2-methylthioclomethiazole聽聽[87764-52-1] and 5-acetyl-4-methyl-2-methylmercaptothiazole聽聽[73548-99-9], resp. The structures of 6 other minor metabolites resulting from side-chain degradation were also elucidated. The occurrence of metabolites with substituents at position 2 of the heterocyclic nucleus was assumed to be initiated by oxidative attack of the N, followed by nucleophilic substitution at position 2. In the experiment, the researchers used many compounds, for example, 4-Methylthiazole-5-carboxylic acid (cas: 20485-41-0Reference of 20485-41-0).

4-Methylthiazole-5-carboxylic acid (cas: 20485-41-0) belongs to thiazole derivatives. Thiazole is a five-membered, unsaturated, planar, 蟺-excessive heteroaromatic containing one sulfur atom and one pyridine-type nitrogen atom at position 3 of the cyclic ring system. Thiazole sulfonation occurs only under forcing conditions: the action of oleum at 250 掳C for 3 hours in the presence of mercury(II) sulfate leads to 65% formation of 5-thiazole sulfonic acid.Reference of 20485-41-0

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

Synthesis of 2-Alkynyl- and 2-Amino-12H-benzothiazolo[2,3-b]quinazolin-12-ones and Their Inhibitory Potential against Monoamine Oxidase A and B was written by Jafari, Behzad;Jalil, Saquib;Zaib, Sumera;Safarov, Sayfidin;Khalikova, Muattar;Khalikov, Djurabay;Ospanov, Meirambek;Yelibayeva, Nazym;Zhumagalieva, Shynar;Abilov, Zharylkasyn A.;Turmukhanova, Mirgul Z.;Kalugin, Sergey N.;Salman, Ghazwan Ali;Ehlers, Peter;Hameed, Abdul;Iqbal, Jamshed;Langer, Peter. And the article was included in ChemistrySelect in 2019.Recommanded Product: 2-Chlorobenzothiazole This article mentions the following:

The 2-alkynyl- and 2-aminobenzothiazolo[2,3-b]quinazolin-12-ones I (R = isopropylaminyl, diphenylaminyl, morpholin-4-yl, etc.) and II (Ar = Ph, 4-tert-butylphenyl, naphthalen-1-yl, etc.) have been synthesized by Palladium catalyzed Buchwald-Hartwig and Sonogashira reactions. Synthesized derivatives were further evaluated for their role as potential inhibitors of monoamine oxidase A and B (MAO-A and B) isoenzymes. Most compounds possess moderate to excellent inhibitory potential against MAO-A and MAO-B. The 2-amino-substituted derivatives show a significantly higher activity as compared to 2-alkynyl- and previously reported 2-aryl derivatives Studied compounds might be employed as novel monoamine oxidase inhibitors and may provide insights for the development of new drug candidates against neurol. diseases. In the experiment, the researchers used many compounds, for example, 2-Chlorobenzothiazole (cas: 615-20-3Recommanded Product: 2-Chlorobenzothiazole).

2-Chlorobenzothiazole (cas: 615-20-3) 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. Various laboratory methods exist for the organic synthesis of thiazoles. Prominent is the Hantzsch thiazole synthesis is a reaction between haloketones and thioamides.Recommanded Product: 2-Chlorobenzothiazole

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

Thiazolopyrimidines was written by Childress, Scott J.;McKee, R. L.. And the article was included in Journal of the American Chemical Society in 1951.Computed Properties of C6H3Cl2N3S This article mentions the following:

The synthesis of the thiazolo[5,4-d]pyrimidines of Weidel and Niemilowicz [Monatsh. 16, 721(1895)], and of Fischer and Ach [Ann. 288, 157(1895)] was extended. The previously reported synthesis of these compounds (Erlenmeyer and Furger, C.A. 41, 5133e) is unreliable. 6-Thiouramil (I) in 20 cc. 85% HCO₂H refluxed 4 hrs., and the product cooled, filtered, dissolved in 35 cc. hot NH₄OH, and precipitated with hot dilute HCl yielded 0.9 g. thiazolo[5,4-d]pyrimidine-5,7-diol (II), did not m. below 360掳. I (1.5 g.) and 15 g. Bz₂O heated 3 hrs. on a steam bath and 30 min. at 170掳 and the product diluted with Et₂O yielded 2.0 g. 2-Ph derivative of II, m. well above 360掳 (decomposition) (from 50% AcOH). II (0.5 g.) and 5 g. POCl₃ heated 12 hrs. at 200掳, and the product cooled and poured over 30 g. ice, filtered, recrystallized from MeOH, and sublimed in vacuo yielded 0.15 g. 5,7-dichlorothiazolo[5,4-d] pyrimidine (III), m. 148.5-9.5掳. The 2-Me derivative (IIIA) of II (3 g.) and 50 g. POCl₃ at 170掳 yielded 2.7 g. 2-Me derivative (IV) of III, white crystals, m. 109-10掳. IV (1 g.) and 15 cc. concentrated NH₄OH heated 4 hrs. at 155掳, and the product chilled and filtered yielded (from 5 combined runs) 1.2 g. 5,7-diamino analog (V), of IV, white crystals from MeOH, m. 255-7掳. V has been submitted for pharmacol. evaluation. Di-Et 4,5-thiazoledicarboxylate (15 g.) and 40 cc. NH₄OH yielded 9 g. 4,5-thiazoledicarboxamide (VI), white crystals from water, m. 298-300掳 (decomposition). Di-Et 2-methyl-4,5-thiazoledicarboxylate (VIA) (8 g.) and 20 cc. concentrated NH₄OH yielded 4 g. 2-methyl-4,5-thiazoledicarboxamide (VII), white crystals from 50% EtOH, m. 296掳 (decomposition). Di-Et 2-phenyl-4,5-thiazoledicarboxylate (3 g.) yielded 2.5 g. diamide (VIII), white crystals from AcOH, m. 319-21掳. Br (1.8 g.) in 28 cc. water at 0掳 containing 3.6 g. KOH added to 2 g. VI, the mixture stirred 3 hrs. at 0掳 with addition of HOBr at intervals, the solution refrigerated overnight, filtered, heated 20 min. at 80掳, and the product precipitated with AcOH yielded 1.3 g. thiazolo[4,5-d]pyrimidine-5,7-diol (IX), did not m. below 360掳. IX (1.5 g.) and 30 g. PCl₅ heated 12 hrs. at 200掳, the product added to 200 g. ice, and the solid filtered off and sublimed in vacuo yielded 0.2 g. product, m. 155-65掳; the filtrate made alk. with NH₃ and the light yellow needles sublimed in vacuo yielded 0.7 g. 6-amino-2,4,5-trichloropyrimidine (X), white crystals, m. 170-1.5掳. X (0.7 g.) and 10 cc. concentrated NH₄OH treated overnight at 100掳, chilled, filtered, the solid leached with hot EtOH, and the residue crystallized from EtO yielded a small amount of 4,6-diamino-2,5-dichloropyrimidine, m. 299-300掳; the alc.-soluble portion yielded 0.3 g. 2,4,6-triamino-5-chloropyrimidine, m. 197-9掳 (from water). VII (2 g.) treated with HOBr yielded 1.7 g. 2-methylthiazolo[4,5-d]pyrimidine-5,7-diol (XA), did not m. below 360掳. VIII (1.8 g.) treated with 56 cc. KOBr did not completely dissolve; the yield was 0.5 g. of the 2-Ph analog of XA, light-cream crystals, m. 331-2掳 (from 50% AcOH). VIA (1 g.) and 5 cc. 85% N₂H₄.H₂O kept 1 hr. in 10 cc. EtOH at room temperature yielded the dihydrazide. VIA (7 g.) in 50 cc. EtOH and 5.3 g. 85% N₂H₄.H₂O heated 48 hrs. at 100掳 and 30 min. at 140掳 yielded 2 g. 2-methylthiazolo-[4,5-d]pyridazine-4,7-diol, pale yellow powder from AcOH and from water, darkened slightly above 300掳, m. 355掳 (decomposition). IIIA (0.7 g.) refluxed with 10 g. BzH and 1 g. ZnCl₂ yielded 0.3 g. 2-styrylthiazolo[5,4-d]pyrimidine-5,7-diol (XI), did not m. below 360掳; XA (0.7 g.) yielded 0.3 g. [4,5-d] isomer of XI, yellow powder, m. 329-31掳 (decomposition). In the experiment, the researchers used many compounds, for example, 5,7-Dichloro-2-methylthiazolo[5,4-d]pyrimidine (cas: 7464-11-1Computed Properties of C6H3Cl2N3S).

5,7-Dichloro-2-methylthiazolo[5,4-d]pyrimidine (cas: 7464-11-1) 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 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.Computed Properties of C6H3Cl2N3S

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

The effect of heat on beef aroma: comparisons of chemical composition and sensory properties was written by MacLeod, Glesni;Ames, Jennifer M.. And the article was included in Flavour and Fragrance Journal in 1986.Safety of 2-Methyl-4,5-dihydrothiazole This article mentions the following:

Aroma volatiles of fresh cooked ground beef subjected to varying degrees of heating were adsorbed on to the adsorbent Tenax TA, and the desorbed aromas analyzed sensorially and chem. Several of the components identified by combined capillary gas chromatog.-mass spectrometry have not been reported previously from heated beef. Data is presented to support the generalization that the higher the degree of heating, the greater the concentrations of aliphatic aldehydes (especially Strecker aldehydes), benzenoids, aliphatic polysulfides, heterocyclic compounds and lipid-derived volatiles, whereas smaller contributions to the isolates arise from aliphatic ketones and alcs. (of non-lipid origin) and aliphatic mono-sulfur components. By sensory anal., eight of odor qualities were frequently used during gas chromatog. odor port assessment, namely buttery, caramel, burnt, green, fragrant, oily/fatty, nutty and meaty. Components associated with the former seven qualities are aroma modifiers whereas compounds contributing meaty quality are character impact compounds, e.g. 2-methyl-3-(methylthio)furan and 3-methylcyclopentanone. Addnl., several unsaturated alicyclic ketones were present which resemble the cyclohexenones previously known to be significant in meat aroma. In the experiment, the researchers used many compounds, for example, 2-Methyl-4,5-dihydrothiazole (cas: 2346-00-1Safety of 2-Methyl-4,5-dihydrothiazole).

2-Methyl-4,5-dihydrothiazole (cas: 2346-00-1) 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. 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.Safety of 2-Methyl-4,5-dihydrothiazole

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

Incompatibility of cefotiam dihydrochloride in parenteral preparations by high-performance liquid chromatography was written by Tanno, Keiki;Ikarashi, Kuniichi;Sasahara, Kazuhisa;Kato, Masami. And the article was included in Japanese Journal of Antibiotics in 1982.Synthetic Route of C18H25Cl2N9O4S3 This article mentions the following:

Changes in external appearance, pH, and residual antimicrobial potency of cefotiam-HCl (I) [66309-69-1] were examined in combination with infusion solutions and other injections. The combination of I with bromhexine-HCl聽聽[611-75-6], dipyridamole聽聽[58-32-2], and gabexate聽mesilate聽聽[56974-61-9] was incompatible because of the turbidity produced. No change was observed in 34 other combinations. In the experiment, the researchers used many compounds, for example, (6R,7R)-7-(2-(2-Aminothiazol-4-yl)acetamido)-3-(((1-(2-(dimethylamino)ethyl)-1H-tetrazol-5-yl)thio)methyl)-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid dihydrochloride (cas: 66309-69-1Synthetic Route of C18H25Cl2N9O4S3).

(6R,7R)-7-(2-(2-Aminothiazol-4-yl)acetamido)-3-(((1-(2-(dimethylamino)ethyl)-1H-tetrazol-5-yl)thio)methyl)-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid dihydrochloride (cas: 66309-69-1) belongs to thiazole derivatives. The thiazole ring is notable as a component of the vitamin thiamine (B1). The nitrogen in thiazole is sp2 hybridized and the lone pair of electrons localized on the nitrogen is less reactive due to increased aromatic character and decreased basicity. It is protonated and alkylated/acylated at nitrogen forming hydrochloride and quaternary thiazolium salt.Synthetic Route of C18H25Cl2N9O4S3

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

Organocatalyst-Mediated Dynamic Kinetic Enantioselective Acylation of 2-Chromanols was written by Glazier, Daniel A.;Schroeder, John M.;Liu, Jitian;Tang, Weiping. And the article was included in Advanced Synthesis & Catalysis in 2018.Synthetic Route of C15H12N2S This article mentions the following:

In this update, a catalytic method for the dynamic kinetic enantioselective acylation of 2-chromanols using benzotetramisole-derived catalysts is reported. High yields and enantiomeric excesses were obtained for a broad range of acylated 2-chromanols, which are important intermediates for the synthesis of various bioactive pharmaceuticals. The high stereoselectivity of the reaction originates from a novel cation-n interaction between the chromanol substrate and the acylated catalyst. In the experiment, the researchers used many compounds, for example, (S)-2-Phenyl-2,3-dihydrobenzo[d]imidazo[2,1-b]thiazole (cas: 950194-37-3Synthetic Route of C15H12N2S).

(S)-2-Phenyl-2,3-dihydrobenzo[d]imidazo[2,1-b]thiazole (cas: 950194-37-3) 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 未 7.27 and 8.77 ppm (C2 and C4), indicating diamagnetic ring current. Thiazole sulfonation occurs only under forcing conditions: the action of oleum at 250 掳C for 3 hours in the presence of mercury(II) sulfate leads to 65% formation of 5-thiazole sulfonic acid.Synthetic Route of C15H12N2S

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

Copper-Catalyzed Three-Component Synthesis of Benzothiazolethiones from o-Iodoanilines, Isocyanide, and Potassium Sulfide was written by Dang, Pan;Zeng, Weilan;Liang, Yun. And the article was included in Organic Letters in 2015.Computed Properties of C7H4FNS2 This article mentions the following:

An efficient copper catalyzed strategy for the synthesis of a variety of benzothiazolethione derivatives has been developed. In the presence of CuCl, the three-component reaction of o-iodoanilines and K₂S with p-toluenesulfonylmethyl isocyanide proceeded smoothly to obtain the corresponding benzothiazolethiones in good to excellent isolated yields. Notably, isocyanide functioned as a carbon source and K₂S functioned as a sulfur source in this reaction. In the experiment, the researchers used many compounds, for example, 6-Fluorobenzo[d]thiazole-2(3H)-thione (cas: 80087-71-4Computed Properties of C7H4FNS2).

6-Fluorobenzo[d]thiazole-2(3H)-thione (cas: 80087-71-4) belongs to thiazole derivatives. Thiazoles are a class of five-membered rings containing nitrogen and sulfur with excellent antitumor, antiviral and antibiotic activities. 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.Computed Properties of C7H4FNS2

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

A new class of chiral pyrrolidine-pyridine conjugate base catalysts for use in asymmetric Michael addition reactions was written by Ishii, Takaaki;Fujioka, Shingo;Sekiguchi, Yusuke;Kotsuki, Hiyoshizo. And the article was included in Journal of the American Chemical Society in 2004.Reference of 132635-95-1 This article mentions the following:

Direct catalytic asym. Michael addition reaction of ketones to nitroolefins, using chiral pyrrolidine-pyridine conjugate bases, e.g., I, as catalysts, is described. The desired 1,4-adducts were obtained in excellent yields with high enantio- and diastereoselectivities. In the experiment, the researchers used many compounds, for example, (S)-Tetrahydro-3H-pyrrolo[1,2-c][1,2,3]oxathiazole 1,1-dioxide (cas: 132635-95-1Reference of 132635-95-1).

(S)-Tetrahydro-3H-pyrrolo[1,2-c][1,2,3]oxathiazole 1,1-dioxide (cas: 132635-95-1) belongs to thiazole derivatives. Thiazole is a five-membered, unsaturated, planar, 蟺-excessive heteroaromatic containing one sulfur atom and one pyridine-type nitrogen atom at position 3 of the cyclic ring system. 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.Reference of 132635-95-1

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

Changes of antibiotic occurrence and hydrochemistry in groundwater under the influence of the South-to-North Water Diversion (the Hutuo River, China) was written by Wang, Jialin;Zhang, Chong;Xiong, Ling;Song, Guangdong;Liu, Fei. And the article was included in Science of the Total Environment in 2022.Quality Control of 4-Amino-N-(thiazol-2-yl)benzenesulfonamide This article mentions the following:

The occurrence of antibiotics in groundwater has significant spatial variability, owing to the complexity of pollutant properties, pollution sources and groundwater recharge and discharge conditions. This study aimed to identify the relationship between antibiotic occurrence and hydrochem. in groundwater. Thus, we undertook this study in a characteristic alluvial-diluvial aquifer where groundwater receives unidirectional recharge from surface water. In total, 47 samples were collected from the Hutuo River before and after an artificial replenishment project. We screened up to four classes of antibiotics and detected 28 types. The statistical anal. of antibiotic concentrations, indicated that there were two pollution areas. Next, we discussed the results pertaining to the occurrence and source of antibiotics by comparing them with hydrochem. data. In the study area, a pos. correlation has been found between inorganic compounds, as SO₄^2-and Cl^–, and the most mobile antibiotics given that both share the same source. This shows that a previous sound geochem. study may provide evidence of the extend of antibiotic occurrence, as in the Hutuo River aquifer. The relationship between antibiotics and hydrochem. in groundwater is determined by recharge sources (rainwater and surface water contaminated with antibiotics). Antibiotics from wastewater treatment plants enter groundwater indirectly through surface water with high SO₄^2- in lightly polluted areas, while in heavily polluted areas, there are high concentrations of inorganic components in garbage leachate and wastewater leakage that carry antibiotics directly into groundwater. In summarized, the relationship between antibiotics and hydrochem. observed in this study shows that a previous sound geochem. study may provide evidence of the extend of antibiotic occurrence. In the experiment, the researchers used many compounds, for example, 4-Amino-N-(thiazol-2-yl)benzenesulfonamide (cas: 72-14-0Quality Control of 4-Amino-N-(thiazol-2-yl)benzenesulfonamide).

4-Amino-N-(thiazol-2-yl)benzenesulfonamide (cas: 72-14-0) belongs to thiazole derivatives. Thiazole is a five-membered, unsaturated, planar, 蟺-excessive heteroaromatic containing one sulfur atom and one pyridine-type nitrogen atom at position 3 of the cyclic ring system. Thiazole sulfonation occurs only under forcing conditions: the action of oleum at 250 掳C for 3 hours in the presence of mercury(II) sulfate leads to 65% formation of 5-thiazole sulfonic acid.Quality Control of 4-Amino-N-(thiazol-2-yl)benzenesulfonamide

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