Day: November 30, 2022

Pappalardo, Giovanni published the artcileIndoles. II. Ultraviolet spectra of ar-mononitro-2,3-dimethylindoles, Category: indole-building-block, the publication is Gazzetta Chimica Italiana (1958), 564-73, database is CAplus.

cf. C.A. 52, 6312f. Ultraviolet spectra of indole (I), skatole (II), and 2,3-dimethylindole (III), and of 4-, 5-, 6-, 7-nitro-2,3-dimethylindoles (IV, V, VI, VII) were measured in C₆H₁₂, alc., 0.05N HCl and 0.05N NaOH and were tabulated. PhNHN:CMeEt cyclized with polyphosphoric acid according to Kissmann, et al. (C.A. 48, 5850e), the product steam-distilled, and the distillate converted to the nitroso derivative, m. 63.5-4.5° (dilute alc.), and reconverted gave pure III, m. 105.5-6.5° (petr. ether). 3-O₂NC₆H₄NHN:CMeEt (12.0 g.) cyclized with concentrated HCl, the product [m. 99.0-9.5° (dilute alc.)] chromatographed in 200 ml. C₆H₆ on Al₂O₃ (Brockmann), eluted successively with C₆H₆ and 1:10 C₅H₅NC₆H₆, and the fractions rechromatographed from C₆H₆ and crystallized gave 2.5 g. IV, m. 176.5-7.5° (C₆H₆ and dilute alc.), and 3.5 g. VI, m. 141-2° (alc.). Cyclization of 4-O₂NC₆H₄NHN:CMeEt [85%, m. 128-9° (dilute alc.)] with concentrated HCl and chromatography in C₆H₆ on Al₂O₃ gave V, m. 193-4°. Similarly 2-O₂NC₆H₄NHNH₂ condensed with MeCOEt gave 63% 2-O₂NC₆H₄NHN:CMeEt, m. 75.5-6.5° (alc.), cyclized with concentrated HCl to VII, m. 162.5-3.5°. The spectrum of III in C₆H₁₂ was similar to that of I and II and the variations were in accord with those predicted on the basis of the effect of Me on the indole system. The notable modifications produced by the introduction of NO₂ groups into the aromatic ring varied according to the position and IV and VI showed certain similarities, though all, with the exception of V, showed bathochromic shifts. The shift was particularly pronounced with VII and the results in general confirmed the hypothesis of significant effects of the NO₂ group on the conjugation of the 2 nuclei, with participation of the hetero atom.

Gazzetta Chimica Italiana published new progress about 20538-12-9. 20538-12-9 belongs to indole-building-block, auxiliary class Indole,Ester,Ether, name is Ethyl 7-methoxy-1H-indole-2-carboxylate, and the molecular formula is C12H13NO3, Category: indole-building-block.

Referemce:
https://www.nature.com/articles/s41429-020-0333-2,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles

Pappalardo, Giovanni published the artcileIndoles. III. Ultraviolet spectra of methoxyindoles and of methoxyindole-2-carboxylic acids and esters, HPLC of Formula: 20538-12-9, the publication is Gazzetta Chimica Italiana (1958), 574-90, database is CAplus.

The ultraviolet spectra of indole (I), 3-, 4-, 5-, 6-, 7-methoxyindoles (II-VI), indole-2-carboxylic acid (VII), 1-, 3-, 4-, 5-, 6-, 7-methoxyindole-2-carboxylic acids (VIII-XIII), VII Et ester (XIV), VIII Me ester (XV), Et 3-, 4-, 5-, 6-, and 7-methoxyindole-2-carboxylates (XVI-XX) were measured in alc. and C₆H₆, and λ_maximum in A. (log ε) were tabulated. II-VI were also measured in 0.05N HCl and 0.05N NaOH. N-Hydroxyindole-2-carboxylic acid (prepared by Na-Hg reduction of ο-O₂NC₆H₄CH₂COCO₂H) methylated with MeI and NaOMe and the product (40%) crystallized (Et₂O-petr. ether) gave VIII, m. 186-7° (dilute Me₂CO), identical with the acid obtained by saponification of XV. XVI saponified in aqueous alkali and the product extracted with Et₂O gave IX, m. 147° (50% MeOH), unstable to exposure to air. Na₂S₂O₅ (2.8 g.) added portionwise to 5 g. 4,2,6-H₂N(O₂N)₂C₆H₂Me (XXI) in 25 ml. HNO₃ (d. 1.52) at 0°, kept 30 min., the solution poured into 50 ml. alc. at 0° containing 0.3 g. CuO, the mixture heated on a steam bath, steam-distilled to remove the 2,6-(O₂N)₂C₆H₃Me (XXII) formed, and the distillate extracted with Et₂O yielded 46% XXII. XXI (4 g.) in 70 ml. concentrated HCl at 0° diazotized with saturated aqueous NaNO₂ (1.5 g.), kept 30 min., treated with 20 ml. 50% H₃PO₂ previously cooled to -5, stirred 1 hr. at 0°, kept 24 hrs. at 0° and the diluted solution steam-distilled yielded 43% XXII. XXII reduced to 2,6-O₂N(H₂N)C₆H₃Me converted to 2,6-O₂N(MeO)C₆H₃Me, transformed to 2,6-O₂N-(MeO)C₆H₃CH₂COCO₂H and reduced with Fe(OH)₂ yielded 65% X, m. 235.5-36° (decomposition). Saponification of XVIII gave a quant. yield of XI, m. 199.5-200°. Reduction of 2,4-O₂N(MeO)C₆H₃CH₂COCO₂H and purification of the product (70%) by repeated precipitation from Et₂O with petr. ether gave crystalline XII, m. 196-7° (alc.). Similarly by the method of Reissert (C.A. 17, 3186) 2,3-O₂N(MeO)C₆H₃CH₂COCO₂H was converted to 65% XIII, m. 181.5-82° (dilute alc.). Esterification of VIII by refluxing in absolute alc. containing 15% dry HCl gave the corresponding Et ester as an unstable oil, and accordingly VIII was similarly esterified in MeOH to 75% XV, m. 67-8° (ligroine). XIV with Me₂SO₄ and NaOH yielded 90% XVI, m. 92-3° (ligroine). X esterified with alc. HCl yielded 83% XVII, m. 171.5-2.5° (dilute alc.). Absolute alc. (100 ml.) containing 1.5 ml. concentrated H₂SO₄ refluxed 10 hrs. with 10 g. 4-MeOC₆H₄NHN:CMeCO₂H [m. 139.5° (C₆H₆)] and the product (20%) crystallized (dilute alc.) gave XVIII, m. 156-6.5°. Esterification of XII with alc. HCl gave 83% ester, crystallized (dilute alc.) to give XIX, m. 135-6°. Similar esterification of XIII yielded 80% XX, m. 113.5-14.5° (after recovery by steam distillation), also produced by cyclization of 2-MeOC₆H₄NHN:CMeCO₂Et (m. 88.5-89°) with AcOH-H₂SO₄. Cyclization with dry HCl gave an unidentified indolic compound, m. 168°. IX (5 g.) and 0.7 g. Cu chromite heated at 200-10° in 30 ml. anhydrous quinoline, the cooled mixture poured onto cracked ice and HCl, extracted with Et₂O, the washed and dried extract evaporated, and the residue distilled at 115-17°/5 mm. and recrystallized (petr. ether) gave II, m. 69.5°; 1,3,5-(O₂N)₃(C₆H₃) addition compound, m. 171-2° (Et₂O). X similarly decarboxylated, extracted with Et₂O, and the product (58%) fractionally crystallized (petr. ether) gave III, m. 69.5-70.5°; picrate, m. 159-60° (C₆H₆). Similarly decarboxylation of XI, XII, and XIII and extraction of the products with Et₂O yielded 70, 40, and 80%, resp. IV, b₂ 124-5°, m. 55.5-56° (petr. ether-EtOH) (picrate, m. 143-3.5°); V, 142-4°, m. 92.5° (petr. ether-EtOH)(picrate, m. 132°); and VI, b₆ 122° [picrate, m. 154-5° (decomposition)]. The introduction of the MeO group more or less distinctly altered the spectral behavior of the indole nucleus owing to the inductive effect of the substituent which, in some instances, was superimposed on the weak mesomeric effects of the indole and indolenine chromophores. The spectral characteristics of the methoxyindole-2-carboxylic acids and esters were related to those of the chromophore-NH(C:C)_nC of pyrrole-2-carboxylic acid with maximum spectral influence when the substituent MeO group was canonically located.

Gazzetta Chimica Italiana published new progress about 20538-12-9. 20538-12-9 belongs to indole-building-block, auxiliary class Indole,Ester,Ether, name is Ethyl 7-methoxy-1H-indole-2-carboxylate, and the molecular formula is C12H13NO3, HPLC of Formula: 20538-12-9.

Referemce:
https://www.nature.com/articles/s41429-020-0333-2,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles

Siltz, Lauren A. Ford published the artcileNew small-molecule inhibitors effectively blocking picornavirus replication, Application In Synthesis of 330161-87-0, the publication is Journal of Virology (2014), 88(19), 11091-11107, 18 pp., database is CAplus and MEDLINE.

Few drugs targeting picornaviruses are available, making the discovery of antivirals a high priority. Here, we identified and characterized three compounds from a library of kinase inhibitors that block replication of poliovirus, coxsackievirus B3, and encephalomyocarditis virus. Using an in vitro translation-replication system, we showed that these drugs inhibit different stages of the poliovirus life cycle. A4(1) inhibited both the formation and functioning of the replication complexes, while E5(1) and E7(2) were most effective during the formation but not the functioning step. Neither of the compounds significantly inhibited VPg uridylylation. Poliovirus resistant to E7(2) had a G5318A mutation in the 3A protein. This mutation was previously found to confer resistance to enviroxime-like compounds, which target a phosphatidylinositol 4-kinase IIIβ (PI4KIIIβ)-dependent step in viral replication. Anal. of host protein recruitment showed that E7(2) reduced the amount of GBF1 on the replication complexes; however, the level of PI4KIIIβ remained intact. E7(2) as well as another enviroxime-like compound, GW5074, interfered with viral polyprotein processing affecting both 3C- and 2A-dependent cleavages, and the resistant G5318A mutation partially rescued this defect. Moreover, E7(2) induced abnormal recruitment to membranes of the viral proteins; thus, enviroxime-like compounds likely severely compromise the interaction of the viral polyprotein with membranes. A4(1) demonstrated partial protection from paralysis in a murine model of poliomyelitis. Multiple attempts to isolate resistant mutants in the presence of A4(1) or E5(1) were unsuccessful, showing that effective broad-spectrum antivirals could be developed on the basis of these compounds

Journal of Virology published new progress about 330161-87-0. 330161-87-0 belongs to indole-building-block, auxiliary class Protein Tyrosine Kinase/RTK,Src, name is SU6656, and the molecular formula is C11H15NO2, Application In Synthesis of 330161-87-0.

Referemce:
https://www.nature.com/articles/s41429-020-0333-2,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles

de Lucas, Ana I. published the artcileScaffold Hopping to Imidazo[1,2-a]pyrazin-8-one Positive Allosteric Modulators of Metabotropic Glutamate 2 Receptor, HPLC of Formula: 642494-36-8, the publication is ACS Omega (2021), 6(35), 22997-23006, database is CAplus and MEDLINE.

Glutamate hyperfunction is implicated in multiple neurol. and psychiatric diseases. Activation of the mGlu2 receptor results in reduced glutamate release and decreased excitability representing a promising novel therapeutic agent for the treatment of disorders such as epilepsy, schizophrenia, mood, anxiety, and other neuropsychiatric disorders. We have previously reported substantial efforts leading to potent and selective mGlu2 PAMs from different chem. series. Herein, the discovery and optimization of a novel series of imidazopyrazinone mGlu2 PAMs are reported. This new scaffold originated from computational searching of fragment databases and comparison with our previously explored scaffolds. Optimization guided by our robust understanding of SAR from former series led to potent, selective, and brain-penetrant compounds

ACS Omega published new progress about 642494-36-8. 642494-36-8 belongs to indole-building-block, auxiliary class Indole,Boronic acid and ester,Indole,Boronate Esters,Boronic acid and ester, name is 6-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-indole, and the molecular formula is C14H18BNO2, HPLC of Formula: 642494-36-8.

Referemce:
https://www.nature.com/articles/s41429-020-0333-2,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles

Appukkuttan, Prasad published the artcileMicrowave enhanced formation of electron rich arylboronates, Application of 6-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-indole, the publication is Synlett (2003), 1204-1206, database is CAplus.

Microwave assisted synthesis of electron rich aminoaryl- and indolylboronates via palladium-catalyzed boronation of the corresponding aryl bromides with bis(pinacolato)diboron are described. Reaction of bis(pinacolato)diboron with 1-bromo-2-R-4-R¹-benzene catalyzed by Pd(dppf)Cl₂ gave under microwave irradiation 2-(2-R-4-R¹-phenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolanes (2a–c, R, R¹: H, NMe₂;, H, NH₂;, NH₂, H). Similar reaction of bromo-1H-indoles XC₈H₆N (5a–d, X = 4-Br, 5-Br, 6-Br, 7-Br) gave the corresponding indolyldioxaborolanes (6a–d). Borylation of tris(4-bromophenyl)amine (3) gave tris[(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]amine (4). Compared to conventional heating conditions, dramatic rate enhancements were found for reactions carried out under microwave irradiation, reducing reaction times from hours or days to only minutes.

Synlett published new progress about 642494-36-8. 642494-36-8 belongs to indole-building-block, auxiliary class Indole,Boronic acid and ester,Indole,Boronate Esters,Boronic acid and ester, name is 6-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-indole, and the molecular formula is C14H18BNO2, Application of 6-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-indole.

Referemce:
https://www.nature.com/articles/s41429-020-0333-2,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles

Hiremath, Shivayogi P. published the artcileSynthesis of 11H-1,2,4-triazolo[4,3-b]pyridazino[4,5-b]indoles, Name: Ethyl 5-bromo-3-formyl-1H-indole-2-carboxylate, the publication is Indian Journal of Heterocyclic Chemistry (1994), 3(3), 145-8, database is CAplus.

4-Oxo-5H-pyridazino[4,5-b]indoles, obtained from the corresponding 3-formylindole-2-carboxylates, were subjected to chlorination to obtain the corresponding 4-chloro-5H-pyridazino[4,5-b]indoles which on reaction with hydrazine hydrate in the presence of K₂CO₃ give 4-hydrazino-5H-pyridazino[4,5-b]indole. The latter were treated with acetic acid/benzoyl chloride to yield the desired title compounds I (R = Me, OMe, Br, OEt, Cl; R¹ = Me, Ph). These compounds were screened for their antimicrobial activity.

Indian Journal of Heterocyclic Chemistry published new progress about 100123-25-9. 100123-25-9 belongs to indole-building-block, auxiliary class Indole,Bromide,Ester,Aldehyde, name is Ethyl 5-bromo-3-formyl-1H-indole-2-carboxylate, and the molecular formula is C12H10BrNO3, Name: Ethyl 5-bromo-3-formyl-1H-indole-2-carboxylate.

Referemce:
https://www.nature.com/articles/s41429-020-0333-2,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles