Chrysomycin A isolated from Streptomyces sp. OA161 is bactericidal to Mycobacterium tuberculosis, methicillin resistant Staphylococcus aureus and vancomycin resistant Enterococcus faecalis.

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New 1,2-dihydropyridine (1,2-DHP)-based fluorophores 1a–1h were designed and synthesized by a one-pot four-component condensation reaction using dienaminodioate, aldehydes, and an in situ-generated hydrazone mediated by trifluoroacetic acid. The photophysical properties of 1,2-DHPs were studied in detail, and a few of them exhibited selective mitochondrial staining ability in HeLa cell lines (cervical cancer cells). A detailed photophysical investigation led to the design of 1,2-DHP 1h as an optimal fluorophore suitable for its potential application as a small molecule probe in the aqueous medium. Also, 1,2-DHP 1h exhibited sixfold enhanced emission intensity than its phosphorylated analogue 1h′ in the long wavelength region (λem ≈ 600 nm), which makes 1,2-DHP 1h′ meet the requirement as a bioprobe for protein tyrosine phosphatases, shown in L6 muscle cell lysate.

A metal-free one-pot cascade annulation of acyclic substrates dienaminodioate, cinnamaldehydes and allyl amine was achieved for the synthesis of polyfunctional biaryl-2-carbaldehydes. The reaction proceeds at room temperature by a trifluoroacetic acid mediated Diels-Alder pathway. Synthetic applications of the resulting biaryl-2-carbaldehyde have been demonstrated by conversion into an array of diverse molecules with biological and materials chemistry relevance. The present work offers a complementary route to the existing metal mediated cross-coupling methods for the preparation of biaryls.

A phenyliodine(III) diacetate mediated umpolung reactivity of the tertiary amines with suitably substituted o-hydroxybenzyl and phenyl groups is exploited to facilitate o-C(sp)-H functionalization to afford diaryl ethers. The presence of an o-CHO and secondary amine functionalities in the resulting diaryl ether, generated in situ, were utilized for synthesis of dibenzoxazepines and dibenzoxazepinones. Mild conditions and relative broad substrate scope, and potential for further diversification of the diaryl ethers are highlights of this methodology.

We report the isolation of two known iridoid glucosides theviridoside (1) and theveside (2) from the aqueous extract of leaves of Cerbera odollam and semi-synthetic derivatisation of theveside prepared in a single step under protection group-free conditions. Derivatives 2a-j were evaluated for cytotoxicity towards five human cancer cell lines of different origins, namely SKBR3 (breast), HeLa (cervical), A375 (skin), HepG2 (liver) and HCT-116 (colon), and IC50 values were determined. Derivatives 2b and 2h exhibited moderate cytotoxicity against HCT-116 and A375 cell lines, respectively.

Diindolylmethane (DIM) is a metabolic product of indole‐3‐carbinol (I3C), the major phytochemicals present in cruciferous vegetables, which can modulate multiple signalling pathways in cancer. The present study deals with the mechanism of action of two synthetic biaryl conjugates of DIM in triple negative breast cancer cells. Out of 12 DIM derivatives tested, two compounds, DIM‐1 and DIM‐4, exhibit cytotoxicity with GI50 values of 9.83 ± 0.2195 μM and 8.726 ± 0.5234 μM, respectively, in 2D culture. In 3D culture, DIM‐1 and DIM‐4 show GI50 values of 24.000 ± 0.7240 μM and 19.230 ± 0.3754 μM, respectively. The non‐toxic nature of the compounds was also established by the toxicity studies using the zebrafish model system. The two compounds induced apoptosis and anoikis in the cancer cells, which was confirmed by morphological analysis, nuclear fragmentation, membrane integrity assay, caspase activity measurements and modulation of pro/anti‐apoptotic proteins. The compounds inhibited cell migration and MMP‐2 and MMP‐9 activities indicating their anti‐metastatic property. They also reduced the expression of active Ras, phosphorylated forms of PI3K, Akt and mTOR. Immunofluorescence studies revealed the reduced expression of EGFR and pEGFR in treated cells. To conclude, DIM‐1 and DIM‐4 induced anti‐breast cancer effects by blocking EGF receptor and subsequently inhibiting Ras‐mediated PI3K‐Akt–mTOR signalling pathway.

A variety of biaryl‐2‐carbaldehydes (III) is readily prepared by reaction of dienes (I) with cinnamaldehydes in the presence of allylamine and TFA.