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The article discusses the synthesis of thiazole-fused tricyclic quinazolinone alkaloids and their derivatives, focusing on compounds found in traditional Chinese and Indian herbal medicine. The authors describe their synthetic program and the successful synthesis of various thiazole-fused tricyclic quinazolinones. The article provides information on the physical and chemical properties of the synthesized compounds, including melting points, yields, and spectral analysis results. This information can be useful for researchers studying these compounds and their potential applications. [Extracted from the article]

SP 1 sp H NMR (300 MHz, acetone- I d i SB 6 sb ): = 11.66 (s, 1 H, H SB N-H sb ), 8.39 (d, I J i = 8.2 Hz, 1 H, H SB 7 sb ), 8.35 (d, I J i = 2.6 Hz, 1 H, H SB 2 sb ), 8.12 (d, I J i = 8.3 Hz, 1 H, H SB 6 sb ). SP 1 sp H NMR (300 MHz, acetone- I d i SB 6 sb ): = 11.49 (s, 1 H, H SB N-H sb ), 8.78 (d, I J i = 2.3 Hz, 1 H, H SB 5 sb ), 8.46 (d, I J i = 2.3 Hz, 1 H, H SB 7 sb ), 8.30 (d, I J i = 2.8 Hz, 1 H, H SB 2 sb ), 8.17-8.07 (m, 2 H, H SB 10or11 sb ), 8.03-7.94 (m, 2 H, H SB 10or11 sb ). SP 13 sp C NMR (75 MHz, acetone- I d i SB 6 sb ): = 157.11 (d, I J i = 15.3 Hz, C SB 4 sb ), 155.38 (dd, I J i = 263.6, 4.4 Hz, Cq), 150.58 (dd, I J i = 253.0, 4.6 Hz, Cq), 148.32 (Cq), 147.54 (C SB 2 sb ), 121.72 (Cq), 120.75 (d, I J i = 3.6 Hz, Cq), 120.03 (Cq), 120.0-104.00 (m, C SB CF sb ). SP 13 sp C NMR (75 MHz, acetone- I d i SB 6 sb ): = 159.44 (C SB 4 sb ), 155.77 (dd, I J i = 266.4, 19.7 Hz, Cq), 150.08 (dd, I J i = 250.8, 15.1 Hz, Cq), 147.14 (C SB 2 sb ), 146.85-146.21 (m, Cq), 122.57-121.48 (m, Cq), 119.05 (dd, I J i = 18.9, 3.4 Hz, C SB 5 sb ), 118.93-114.64 (m, Cq), 119.00-105.00 (m, C SB CF sb ). SP 13 sp C NMR (75 MHz, acetone- I d i SB 6 sb ): = 159.91 (dt, I J i = 252.3, 5.2 Hz, C SB 6 sb ), 157.63 (d, I J i = 3.8 Hz, C SB 4 sb ), 147.42 (Cq), 146.79 (C SB 2 sb ), 133.10 (d, I J i = 7.3 Hz, Cq), 126.29-125.29 (m, C SB 5,7,8 sb ),, 123.00-105.00 (m, C SB CF sb ). [Extracted from the article]

Removal of the cyano group on the thiazole ring was performed by heating 2-cyanobenzothiazoles B III b and B IV b in HCl (37% in water) for 45 minutes to yield the corresponding carbonitrile-free analogues B IIIa b and B IVa b in yields of 53% and 25%, respectively, respectively. Thus, in the presence of KI, the cyclization of cyanothioformanilide B 3c b led to benzothiazole B VI b (13% yield), together with the corresponding isothiocyanate B 4c b , being the major product in 37% yield (Table 4, entry 1). HRMS (EI SP + sp ): I m i / I z i [M + H] SP + sp calcd for C SB 9 sb H SB 9 sb N SB 2 sb O SB 2 sb S: 209.0385; found: 209.0388. HRMS (EI SP + sp ): I m i / I z i [M + H] SP + sp calcd for C SB 9 sb H SB 9 sb N SB 2 sb O SB 2 sb S: 209.0385; found: 209.0378. [Extracted from the article]

In order to prepare an array of β-cyanoenamine derivatives as potential precursors of heterocyclic systems with pharmaceutical interest, the synthesis of fifteen polyfunctionalized 4 H -chromenes was realized via a microwave-assisted and catalyst-free three-component reaction. Microwave-heated reactions were monitored by Raman spectroscopy, enabling a fast and efficient setting of the process parameters. This study confirms that this monitoring tool may have some limitations linked to homogeneity of reaction medium. This work also investigates the use of some bio-sourced and sustainable solvents currently studied in many works. Ethanol remains the most suitable for this synthesis. [ABSTRACT FROM AUTHOR]

The synthesis of a new library of polyheterocyclic 11 H -pyrido[2,1- b ]quinazolin-11-one derivatives was investigated. Satisfactory conditions were obtained via sequential C–N Buchwald–Hartwig coupling and pyridine dearomatization. In this work, traditional solvents were replaced by the bio-sourced eucalyptol, confirming the interest in it as a green solvent in chemistry. [ABSTRACT FROM AUTHOR]

C-C Bond formation from direct C-H activation is now recognized as a powerful and straightforward strategy for the synthesis of complex molecules and especially for late-stage functionalization. Many of these reactions allow a streamlined route to bi(hetero)aryl compounds with applications in medicinal chemistry as well as in organic materials. Since high temperatures and long reaction times are often required for C-H activation, microwave irradiation has emerged as a suitable tool. This short review gives an overview of the metal-catalyzed C-H functionalization of heteroarenes since 2013 and highlights the benefits of microwave irradiation over traditional heating. 1 Introduction 2 Palladium-Catalyzed Direct Functionalization of sp² C-H Bonds with Aryl Halides 3 Palladium-Catalyzed and Silver-Assisted Direct Arylation of sp² C-H Bonds with Aryl Halides 4 Palladium-Catalyzed and Copper-Assisted Direct Arylation of sp² C-H Bonds with Aryl Halides 5 Copper-Catalyzed sp³-sp² C-C Bond Formation 6 Conclusion [ABSTRACT FROM AUTHOR]

A novel method for the synthesis of anthranilate esters is described. The esterification reaction of nitro-substituted anthranilic acids was carried out under microwave irradiation. A range of solvents and other reaction parameters were investigated to provide the most environmentally friendly reaction conditions. The feasibility of scale-up was demonstrated, allowing a simple and inexpensive production of anthranilate esters. [ABSTRACT FROM AUTHOR]