Month: April 2022

The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Ninhydrin-positive components derived from cystine during the cyanide-nitroprusside test》. Authors are Hambraeus, Leif; Reio, Lembitu.The article about the compound:2-Amino-4,5-dihydrothiazole-4-carboxylic acidcas:2150-55-2,SMILESS:O=C(C1N=C(N)SC1)O).Product Details of 2150-55-2. Through the article, more information about this compound (cas:2150-55-2) is conveyed.

NaCN used in the cyanide-nitroprusside test of Brand et. al to determine cystine (I) in urine (CA 24, 3555) could be effectively replaced by NaBH4 which yielded about the same color intensity as when NaCN was used. However, the color produced by NaBH4 faded very quickly. Studies were made to obtain some qual. and quant. data regarding the ninhydrin-pos. components during the reaction between NaCN, I, and Na nitroprusside by means of an automatic amino acid analyzer. When freshly prepared com. NaCN was used, 2 peaks were obtained (one of I and cysteine). With the addition of NaCN and I, no addnl. peak was found, but a new peak appeared which corresponded to 4-carboxythiazolidinon-2-imide (II) formed due to the cleavage of I. With pure I, peaks of II and another peak of 2-aminothiazoline-4-carboxylic acid appeared.

There are many compounds similar to this compound(2150-55-2)Product Details of 2150-55-2. if you want to know more, you can check out my other articles. I hope it will help you，maybe you’ll find some useful information.

Reference:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Recommanded Product: Ethyl oxazole-5-carboxylate. The mechanism of aromatic electrophilic substitution of aromatic heterocycles is consistent with that of benzene. Compound: Ethyl oxazole-5-carboxylate, is researched, Molecular C6H7NO3, CAS is 118994-89-1, about Light-Promoted Copper-Catalyzed Enantioselective Alkylation of Azoles. Author is Li, Chen; Chen, Bin; Ma, Xiaodong; Mo, Xueling; Zhang, Guozhu.

A catalytic asym. alkylation of azoles with secondary 1-arylalkyl bromides through direct C-H functionalization is reported. Under blue-light photoexcitation, a copper(I)/carbazole-based bisoxazoline (CbzBox) catalytic system exhibits good reactivity and high stereoselectivity, thus offering an efficient strategy for the construction of chiral alkyl azoles. These reactions proceed at low temperature and are compatible with a wide range of azoles.

There are many compounds similar to this compound(118994-89-1)Recommanded Product: Ethyl oxazole-5-carboxylate. if you want to know more, you can check out my other articles. I hope it will help you，maybe you’ll find some useful information.

Reference:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

The three-dimensional configuration of the ester heterocycle is basically the same as that of the carbocycle. Compound: 4-Bromo-1-methyl-2-nitro-1H-imidazole(SMILESS: O=[N+](C1=NC(Br)=CN1C)[O-],cas:121816-79-3) is researched.Synthetic Route of C5H5FN2. The article 《Synthesis and hypoxia-selective cytotoxicity of a 2-nitroimidazole mustard》 in relation to this compound, is published in Bioorganic & Medicinal Chemistry Letters. Let’s take a look at the latest research on this compound (cas:121816-79-3).

A four-step synthesis of 5-[N,N-bis(2-chloroethyl)amino]-1-methyl-2-nitroimidazole from 1-methyl-2-nitroimidazole is described. This compound showed similar hypoxia-selective cytotoxicity to the dinitrobenzamide mustard SN 23862 in UV4 cells (ca. 40-fold), and superior selectivity (>7-fold) in repair-competent AA8 cells.

There are many compounds similar to this compound(121816-79-3)Reference of 4-Bromo-1-methyl-2-nitro-1H-imidazole. if you want to know more, you can check out my other articles. I hope it will help you，maybe you’ll find some useful information.

Reference:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of C5H5FN2. So far, in addition to halogen atoms, other non-metallic atoms can become part of the aromatic heterocycle, and the target ring system is still aromatic. Compound: 5-Amino-2-fluoropyridine, is researched, Molecular C5H5FN2, CAS is 1827-27-6, about Synthesis of 6-substituted pyrido[3,4-d]pyrimidin-4(3H)-ones via directed lithiation of 2-substituted 5-aminopyridine derivatives.

Directed lithiation of Boc or pivaloyl derivatives of 2-substituted 5-aminopyridines I (R = Cl, F, OMe, R1 = COnCMe3, X = H, n = 1, 2) with BuLi-TMEDA in di-Et ether at -10°C gave 4-lithio derivatives which were quenched with CO2 to give the analogous C-4 carboxylic acids I (X = CO2H). Hydrolysis of the protecting groups with either TFA or aqueous KOH gave 2-substituted 5-aminopyridine-4-carboxylic acids I (R1 = H, X = CO2H) which were converted to 6-substituted pyrido[3,4-d]pyrimidin-4(3H)-ones II by reaction with formamide or, more optionally, formamidine acetate. Boc protected aminopyridines provided the best overall results, with synthesis of these derivatives best achieved by direct reaction of the aminopyridine with di-tert-Bu dicarbonate in the absence of added base.

There are many compounds similar to this compound(1827-27-6)Synthetic Route of C5H5FN2. if you want to know more, you can check out my other articles. I hope it will help you，maybe you’ll find some useful information.

Reference:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Most of the compounds have physiologically active properties, and their biological properties are often attributed to the heteroatoms contained in their molecules, and most of these heteroatoms also appear in cyclic structures. A Journal, Article, Molecules called Energetic and Geometric Characteristics of the Substituents: Part 2: The Case of NO2, Cl, and NH2 Groups in Their Mono-Substituted Derivatives of Simple Nitrogen Heterocycles, Author is Wieczorkiewicz, Pawel A.; Szatylowicz, Halina; Krygowski, Tadeusz M., which mentions a compound: 591-54-8, SMILESS is C1=CN=CN=C1N, Molecular C4H5N3, Safety of 4-Aminopyrimidine.

Variously substituted N-heterocyclic compounds are widespread across bio- and medicinal chem. The work aims to computationally evaluate the influence of the type of N-heterocyclic compound and the substitution position on the properties of three model substituents: NO2, Cl, and NH2. For this reason, the energetic descriptor of global substituent effect (Erel), geometry of substituents, and electronic descriptors (cSAR, pEDA, sEDA) are considered, and interdependences between these characteristics are discussed. Furthermore, the existence of an endocyclic N atom may induce proximity effects specific for a given substituent. Therefore, various quantum chem. methods are used to assess them: the quantum theory of atoms in mols. (QTAIM), anal. of non-covalent interactions using reduced d. gradient (RDG) function, and electrostatic potential maps (ESP). The study shows that the energetic effect associated with the substitution is highly dependent on the number and position of N atoms in the heterocyclic ring. Moreover, this effect due to interaction with more than one endo N atom (e.g., in pyrimidines) can be assessed with reasonable accuracy by adding the effects calculated for interactions with one endo N atom in substituted pyridines. Finally, all possible cases of proximity interactions for the NO2, Cl, and NH2 groups are thoroughly discussed.

There are many compounds similar to this compound(591-54-8)Safety of 4-Aminopyrimidine. if you want to know more, you can check out my other articles. I hope it will help you，maybe you’ll find some useful information.

Reference:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Quality Control of 5-Amino-2-fluoropyridine. Aromatic compounds can be divided into two categories: single heterocycles and fused heterocycles. Compound: 5-Amino-2-fluoropyridine, is researched, Molecular C5H5FN2, CAS is 1827-27-6, about Copper-Catalyzed Electrochemical C-H Amination of Arenes with Secondary Amines. Author is Yang, Qi-Liang; Wang, Xiang-Yang; Lu, Jia-Yan; Zhang, Li-Pu; Fang, Ping; Mei, Tian-Sheng.

Electrochem. oxidation represents an environmentally friendly solution to conventional methods that require caustic stoichiometric chem. oxidants. However, C-H functionalizations merging transition-metal catalysis and electrochem. techniques are, to date, largely confined to the use of precious metals and divided cells. Herein, the authors report the 1st examples of Cu-catalyzed electrochem. C-H aminations of arenes at room temperature using undivided electrochem. cells, thereby providing a practical solution for the construction of arylamines. The use of Bu4NI as a redox mediator is crucial for this transformation. From mechanistic studies including kinetic profiles, isotope effects, cyclic voltammetric analyses, and radical inhibition experiments, the reaction appears to proceed via a single-electron-transfer (SET) process, and a high valent Cu(III) species is likely involved. These findings provide a new avenue for transition-metal-catalyzed electrochem. C-H functionalization reactions using redox mediators.

There are many compounds similar to this compound(1827-27-6)Quality Control of 5-Amino-2-fluoropyridine. if you want to know more, you can check out my other articles. I hope it will help you，maybe you’ll find some useful information.

Reference:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Recommanded Product: 2-Amino-4,5-dihydrothiazole-4-carboxylic acid. The protonation of heteroatoms in aromatic heterocycles can be divided into two categories: lone pairs of electrons are in the aromatic ring conjugated system; and lone pairs of electrons do not participate. Compound: 2-Amino-4,5-dihydrothiazole-4-carboxylic acid, is researched, Molecular C4H6N2O2S, CAS is 2150-55-2, about Analysis of the cyanide metabolite 2-aminothiazoline-4-carboxylic acid in urine by high-performance liquid chromatography. Author is Lundquist, Per; Kagedal, Bertil; Nilsson, Lennart; Rosling, Hans.

The cyanide metabolite 2-aminothiazoline-4-carboxylic acid (ATC) was converted to N-carbamylcysteine and analyzed by high-performance liquid chromatog. (HPLC) and fluorometric detection. ATC was first separated from interfering substances by passing through the cation exchanger AG 50W-X8. Interfering disulfides were converted to thiols by reduction of the eluate with thiopropyl-Sepharose 6B. The thiols were then adsorbed to the organomercurial adsorbent p-acetoxymercurianiline-Sepharose 4B while ATC was obtained in the effluent. ATC was then converted to N-carbamylcysteine by ring opening at high temperature in an alk. environment. Derivatization of N-carbamylcysteine was with N-(7-dimethylamino-4-methyl-3-coumarinyl)maleimide. The imprecision (CV) of the method was 3.6% and the anal. recovery was quant. The detection limit was 0.3 μM. ATC in urine was stable for at least 3 mo when stored at -196 to +20 °C. The ATC concentration in urine was below the limit of detection in healthy nonsmokers. The utility of the method was demonstrated by the finding of up to 10.5 μM ATC concentrations in urine samples from human subjects in Mozambique living on a high dietary intake of cyanide from the cassava root. In a metabolic study rats were exposed to acetonitrile in the drinking water. After 4 wk very high ATC levels were found in the urine, representative values from two rats being 195 and 525 μM, resp.

There are many compounds similar to this compound(2150-55-2)Recommanded Product: 2-Amino-4,5-dihydrothiazole-4-carboxylic acid. if you want to know more, you can check out my other articles. I hope it will help you，maybe you’ll find some useful information.

Reference:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

COA of Formula: C4H5N3. The reaction of aromatic heterocyclic molecules with protons is called protonation. Aromatic heterocycles are more basic than benzene due to the participation of heteroatoms. Compound: 4-Aminopyrimidine, is researched, Molecular C4H5N3, CAS is 591-54-8, about Reductive Amination Revisited: Reduction of Aldimines with Trichlorosilane Catalyzed by Dimethylformamide – Functional Groups Tolerance, Scope, and Limitations. Author is Popov, Kirill K.; Campbell, Joanna L. P.; Kysilka, Ondrej; Hosek, Jan; Davies, Christopher D.; Pour, Milan; Kocovsky, Pavel.

Aldimines R1CH2NHR2 (R1 = but-3-yn-1-yl, Ph, thiophen-2-yl, etc.; R2 = Bu, Bn, cyclohexyl, 5-methyl-1,3,4-thiadiazol-2-yl, etc.), generated in situ from aliphatic, aromatic, and heteroaromatic aldehydes R1CHO and aliphatic, aromatic, and heteroaromatic primary or secondary amines R2NH2, can be reduced with trichlorosilane in the presence of DMF (DMF) as an organocatalyst (≤10 mol%) in toluene or CH2Cl2 at room temperature The reduction tolerates ketone carbonyls, esters, amides, nitriles, sulfones, sulfonamides, NO2, SF5, and CF3 groups, boronic esters, azides, phosphine oxides, C=C and CC bonds, and ferrocenyl nucleus but sulfoxides and N-oxides are reduced. α,β-Unsaturated aldimines undergo 1,2-reduction only, leaving the C=C bond intact. N-Monoalkylation of primary amines is attained with a 1:1 aldehyde to amine ratio, whereas excess of the aldehyde (≥2:1) allows second alkylation, giving rise to tertiary amines. Reductive N-alkylation of α-amino acids proceeds without racemization; the resulting products, containing a CC bond or N3 group, are suitable for click chem. This reaction thus offers advantages over the traditional methods (borohydride reduction or catalytic hydrogenation) in terms of efficiency and chemoselectivity. Solubility of some of the reacting partners appears to be the only limitation. The byproducts generated by the workup with aqueous NaHCO3 (i.e., NaCl and silica) are environmentally benign. As a greener alternative, DMA can be employed as a catalyst instead of DMF.

I hope my short article helps more people learn about this compound(4-Aminopyrimidine)COA of Formula: C4H5N3. Apart from the compound(591-54-8), you can read my other articles to know other related compounds.

Reference:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

HPLC of Formula: 118994-89-1. Aromatic heterocyclic compounds can also be classified according to the number of heteroatoms contained in the heterocycle: single heteroatom, two heteroatoms, three heteroatoms and four heteroatoms. Compound: Ethyl oxazole-5-carboxylate, is researched, Molecular C6H7NO3, CAS is 118994-89-1, about Total synthesis of potent antifungal marine bisoxazole natural products benzazoles A and B. Author is Bull, James A.; Balskus, Emily P.; Horan, Richard A. J.; Langner, Martin; Ley, Steven V..

The bengazoles are a family of marine natural products that display potent antifungal activity and a unique structure, containing two oxazole rings flanking a single carbon atom. Total syntheses of benzazole A and B are described, which contain a sensitive stereogenic center at this position between the two oxazoles. Addnl., the synthesis of 10-epi-benzazole A is reported. Two parallel synthetic routes were investigated, relying on construction of the 2,4-disubstituted oxazole under mild conditions and a diastereoselective 1,3-dipolar cycloaddition Our successful route is high yielding, provides rapid access to single stereoisomers of the complex natural products and allows the synthesis of analogs for biol. evaluation.

I hope my short article helps more people learn about this compound(Ethyl oxazole-5-carboxylate)HPLC of Formula: 118994-89-1. Apart from the compound(118994-89-1), you can read my other articles to know other related compounds.

Reference:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Quality Control of 4-Aminopyrimidine. The mechanism of aromatic electrophilic substitution of aromatic heterocycles is consistent with that of benzene. Compound: 4-Aminopyrimidine, is researched, Molecular C4H5N3, CAS is 591-54-8, about Racemization-free synthesis of dipeptide, amide and ester by oxalyl chloride and catalytic triphenylphosphine oxide. Author is Ren, Ji-Wei; Tong, Meng-Nan; Zhao, Yu-Fen; Ni, Feng.

An efficient triphenylphosphine oxide (Ph3PO) catalyzed amidation and esterification reaction for rapid synthesis of a series of dipeptides, amides and esters under mild condition is described. This reaction is applicable to challenging couplings of hindered carboxylic acid with low nucleophilic amine or alc., giving products in good yields (67-90%) without any racemization. This system employs highly reactive intermediate Ph3PCl2 as activator of carboxylate, in a catalytic manner, and drive the reaction to complete in short reaction time (less than 10 min). It has the advantages of good functional group tolerance, broad substrate scope and good atom-economy. A 100 mmol scale reaction with good yield shed light on its potential for industrial application. A plausible mechanism is proposed based on 31P NMR monitor of reaction process.

I hope my short article helps more people learn about this compound(4-Aminopyrimidine)Quality Control of 4-Aminopyrimidine. Apart from the compound(591-54-8), you can read my other articles to know other related compounds.

Reference:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem