Two BODIPY-biotin conjugates and are designed and synthesized for targeted PDT applications. Both have good absorption with a high molar absorption coefficient and decent singlet oxygen generation quantum yields. The photosensitizers and were found to be localized in the mitochondria with excellent photocytotoxicity of up to 18.
View Article and Find Full Text PDFA Pd(ii)-catalyzed oxidative alkenylation of 4-hydroxycoumarins with maleimides for the synthesis of 4-hydroxy-3-maleimidecoumarins has been described. This methodology proceeds via C-H activation and C(sp2)-C(sp2) bond formation providing a series of alkenylated Heck-type products.
View Article and Find Full Text PDFOrganophosphorus compounds are important structural motifs that unveil enormous applications, particularly in the field of organic synthesis, agriculture, materials science and medicinal chemistry. Additionally, ortho-substituted arylphosphorus compounds have played an important role in homogeneous catalysis. Though there are several synthetic pathways for the synthesis of organophosphorus compounds, this review is particularly focused on aryne-based methodologies reported in the literature to date.
View Article and Find Full Text PDFA Pd(II)-catalyzed oxidative annulation reaction of 4-hydroxycoumarin and arylcarboxylic acid via double C-H bond activations has been accomplished for the synthesis of bis-coumarins. This synthetic strategy provides a wide range of structurally diversified bis-coumarins in moderate to good yields with a variety of functional group compatibility. Moreover, photophysical properties of synthesized bis-coumarins have been evaluated, which reveals their interesting fluorescent properties.
View Article and Find Full Text PDFCorrection for 'A metal-free cascade reaction of β-halo-α,β-unsaturated aldehydes and 1,4-dithiane-2,5-diols: synthesis of polycyclic 2-formylthiophenes' by Limi Goswami et al., Org. Biomol.
View Article and Find Full Text PDFA novel transition-metal free synthetic strategy has been developed for the direct synthesis of quaternary phosphonium triflates via insertion of aryne into phosphine oxide. This methodology provides good yields of quaternary phosphonium salts and one of the synthesized phosphonium salts has been unambiguously established by single crystal XRD study. Preliminary mechanistic studies suggest that the reaction proceeds via a sequential [2 + 2] cycloaddition followed by the o-arylation and protonation pathway.
View Article and Find Full Text PDFA transition-metal-free coupling reaction of aryne, DMSO, and activated alkyne for the synthesis of 2-[( o-methylthio)aryloxy]-substituted dialkyl maleates is reported. This cascade process is associated with several bond cleavage as well as bond formation reactions in one pot. One of our synthesized maleates has been unambiguously established by single-crystal XRD studies.
View Article and Find Full Text PDFMycobacterium tuberculosis infection causes 1.8 million deaths worldwide, of which half a million has been diagnosed with resistant tuberculosis (TB). Emergence of multi drug resistant and extensive drug resistant strains has made all the existing anti-TB therapy futile.
View Article and Find Full Text PDFA cascade synthetic strategy for the direct synthesis of 2-aroyl benzofurans from aryne precursors has been developed. This reaction proceeds via C-O and C-C bond cleavage as well as C-O and C-C bond formation in a single reaction vessel. The methodology provides good yields of 2-aroyl benzofurans and tolerates a variety of functional groups.
View Article and Find Full Text PDFA metal-free cascade reaction strategy has been developed for the synthesis of novel polycyclic 2-formylthiophenes from β-halo-α,β-unsaturated aldehydes and 1,4-dithiane-2,5-diols. A recyclable polymer supported organic base was used to perform the reaction process. This synthetic protocol was applied to synthesize several novel polycyclic thiophenes including steroidal D-ring annelated thiophene.
View Article and Find Full Text PDFA novel transition-metal-free direct synthesis of 3-substituted isocoumarin from 4-hydroxycoumarin and a benzyne precursor is developed. This synthetic strategy proceeds via C-O and C-C bond cleavage as well as C-O and C-C bond formations in a single reaction vessel by simple treatment with CsF in the absence of catalyst. This methodology affords moderate to good yields of 3-substituted isocoumarins and is tolerant of a variety of functional groups including halide.
View Article and Find Full Text PDFA palladium catalyzed cascade reaction of 4-hydroxycoumarins and in situ generated arynes has been developed for the direct synthesis of coumestans. This cascade strategy proceeds via C-H bond activation/C-O and C-C bond formations in a single reaction vessel. This methodology affords moderate to good yields of coumestans and is tolerant of a variety of functional groups including halide.
View Article and Find Full Text PDFThis article reports for the first time a facile, green synthesis of 2D CuO nanoleaves (NLs) using the amino acid, namely aspartic acid, and NaOH by a microwave heating method. The amino acid acts as a complexing/capping agent in the synthesis of CuO NLs. This method resulted in the formation of self-assembled 2D CuO NLs with an average length and width of ~300-400 and ~50-82 nm, respectively.
View Article and Find Full Text PDFA novel heterogeneous catalytic hydrogenation-hydrogenolysis strategy has been developed for the α-methylation of ketones via enaminones using DMF dimethyl acetal as carbon source. This strategy provides a very convenient route to α-methylated ketones using a variety of ketones without any base or oxidant.
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