Background: Growing concerns about sustainability have driven the search for eco-friendly pest management solutions. Combining natural and synthetic compounds within controlled release systems is a promising strategy. This study investigated the co-encapsulation of the natural compound citral (Cit) and the synthetic antifungal cyproconazole (CPZ) using two water-based nanocarriers: solid lipid nanoparticles (SLNs) and chitosan nanoparticles (CSNPs).
View Article and Find Full Text PDFIn the present work, derivatives of phenanthridine-6(5)-ones and benzo[]chromenes were efficiently prepared through an intramolecular C-H bond functionalization reaction catalyzed by photochemically synthesized Pd-PVP nanoparticles. The heterocycles were obtained intramolecular arylation of the corresponding -methyl--aryl-2-halobenzamide or aryl-(2-halo)benzyl ethers using KCO as base in a mixture of HO : DMA as solvent without additives or ligands. High yields of the heterocyclic compounds were achieved (up to 95%) using a moderately low catalyst loading (1-5 mol%) under an air atmosphere at 100 °C.
View Article and Find Full Text PDFWe prepared a series of free NH and N-substituted dibenzonthiazines with potential anti-tumor activity from N-aryl-benzenesulfonamides. A biological test of synthesized compounds (59 samples) was performed in vitro measuring their antiproliferative activity against a panel of six human solid tumor cell lines and its tubulin inhibitory activity. We identified 6-(phenylsulfonyl)-6H-dibenzo[c,e][1,2]thiazine 5,5-dioxide and 6-tosyl-6H-dibenzo[c,e][1,2]thiazine 5,5-dioxide as the best compounds with promising values of activity (overall range of 2-5.
View Article and Find Full Text PDFNovel approaches for N- and O-desulfonylation under room temperature (rt) and transition-metal-free conditions have been developed. The first methodology involves the transformation of a variety of -sulfonyl heterocycles and phenyl benzenesulfonates to the corresponding desulfonylated products in good to excellent yields using only KOBu in dimethyl sulfoxide (DMSO) at rt. Alternately, a visible light method has been used for deprotection of -methyl--arylsulfonamides with Hantzsch ester (HE) anion serving as the visible-light-absorbing reagent and electron and hydrogen atom donor to promote the desulfonylation reaction.
View Article and Find Full Text PDFA novel approach for the synthesis of tetracyclic indoles and 7-azaindoles is reported. The strategy involves four steps, with a fast rt intramolecular α-arylation of ketones as key step. The reaction was inspected synthetically to achieve the synthesis of 11 novel tetracyclic structures with moderate to very good yields (39-85%).
View Article and Find Full Text PDFA new and general synthetic route to prepare dibenzosultams is here reported. This approach involves the synthesis of N-aryl-2-halobenzenesulfonamides (3), followed by intramolecular C-C photoinduced arylation under soft conditions without the use of "Transition Metal". The photostimulated reactions exhibit very good tolerance to different substituent groups with good to excellent isolated yields (42-98%) of products.
View Article and Find Full Text PDFAn efficient and simple protocol for the preparation of a series of 9H-carbazoles by photostimulated SRN1 substitution reactions is presented. Substituted 9H-carbazoles were synthesized in low to excellent yields (up to 96%) through an intramolecular C–N bond formation of 2′-halo[1,1′-biphenyl]-2-amines by the photoinitiated SRN1 mechanism under mild and “transition-metal-free” conditions. The biphenylamines used as substrates were obtained with isolated yields ranging from 21% to 84% by two approaches: (A) the cross-coupling Suzuki–Miyaura reaction and (B) the radical arylation of anilines.
View Article and Find Full Text PDFThe synthesis of a series of 6-substituted 2-pyrrolyl and 2-indolyl benzoxazoles by photostimulated C-O cyclization of anions from 2-pyrrole carboxamides, 2-indole carboxamides, or 3-indole carboxamides has been found to proceed in good to excellent yields (41-100%) in DMSO and liquid ammonia. The pyrrole and indole carboxamides are obtained in good to very good isolated yields by an amidation reaction of different 2-haloanilines with 2-carboxylic acid of pyrrole and 2- or 3-carboxylic acid of indole. To explain the regiochemical outcome of these reactions (C-O arylation vs C-N or C-C arylation), a theoretical analysis was performed using DFT methods and the B3LYP functional.
View Article and Find Full Text PDFA general synthetic route to prepare all four carboline regioisomers by photostimulated cyclization of anilinohalopyridines is described. The methodology affords various substituted carbolines in good to excellent yields. In the case of α-carbolines, the S(RN)1 methodology complements previously reported palladium-catalyzed cyclization approaches.
View Article and Find Full Text PDFThe photostimulated intramolecular ortho-arylation reactions of bromoarenes linked with pendant phenoxy containing N-substituted tetrahydroisoquinolines in liquid ammonia afforded aporphine (54-82% yield) alkaloid derivatives via SRN1 reactions. This strategy was extended for the first time to the synthesis of a homoaporphine derivative (40% yield). Tetrahydroisoquinoline precursors that contained electron-withdrawing groups on nitrogen (i.
View Article and Find Full Text PDF2-Substituted indoles (5a,b and 7) and fused indoles (9a-c, 11a,b, and 12) have been obtained by the S(RN)1 mechanism from photostimulated reactions of o-iodoaniline (1) and 1-halo-2-naphthalen-2-ylamines (3a,b) with enolate ions of acyclic (acetophenone (6), 2- (4a) and 4-acetylpyridine (4b)) and cyclic ketones (1- (8a) and 2-indanone (10a), 1- (8b) and 2-tetralone (10b) and 1-benzosuberone (8c)) in DMSO and liquid ammonia as solvents. The carbanions derived from 4a,b, 8a, and 10b are novel nucleophiles that form new C-C bonds by the S(RN)1 mechanism.
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