Organ printing can be defined as layer-by-layer additive robotic biofabrication of three-dimensional functional living macrotissues and organ constructs using tissue spheroids as building blocks. The microtissues and tissue spheroids are living materials with certain measurable, evolving and potentially controllable composition, material and biological properties. Closely placed tissue spheroids undergo tissue fusion - a process that represents a fundamental biological and biophysical principle of developmental biology-inspired directed tissue self-assembly. It is possible to engineer small segments of an intraorgan branched vascular tree by using solid and lumenized vascular tissue spheroids. Organ printing could dramatically enhance and transform the field of tissue engineering by enabling large-scale industrial robotic biofabrication of living human organ constructs with "built-in" perfusable intraorgan branched vascular tree. Thus, organ printing is a new emerging enabling technology paradigm which represents a developmental biology-inspired alternative to classic biodegradable solid scaffold-based approaches in tissue engineering.

Organ Printing: Tissue Spheroids as Building Blocks

Synthetic potential of the tertiary-amine-catalysed reaction of activated vinyl carbanions with aldehydes

This work was supported by the Foundation for Science and Technology (FCT), Portugal (projects PTDC/QUI-QUI/113687/2009 and PEst-C/QUI/UI0081/2013). A.G. (SFRH/BD/43531/2008) and M.J.M. (SFRH/BD/61262/2009) thank FCT for grants.

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Chromone: A Valid Scaffold in Medicinal Chemistry

o-Quinone methides: intermediates underdeveloped and underutilized in organic synthesis

https://www.ircc.iitb.ac.in/IRCC-Webpage/rnd/PDF/Awards11KothaS.pdf

Transition Metal Catalyzed (2+2+2) Cycloaddition and Application in Organic Synthesis

On the claisen rearrangement of 1,4-diaryloxy-2-butynes

o-Haloaryl allenylmethyl ethers and amines upon treatment with n-Bu3SnH and AIBN in refluxing benzene, underwent a 5-exo-trig free radical cyclisation to give the respective 3-ethenyl-2,3-dihydrobenzofurans and 3-ethenyl-2,3-dihydroindoles in good yields.

Radical Cyclisation of o-Haloaryl Allenylmethyl Ethers and Amines: Synthesis of 3-Ethenyl-2,3-dihydrobenzofurans and 3-Ethenyl-2,3-dihydroindoles

Intramolecular substitutions leading to cyclizations with the ejection of chlorine have been noticed during mass spectral fragmentation of 4-chloro-3-(N-aryliminomethyl) (2H) benzopyrans and benzothiopyrans. Very interesting ortho effects involving intramolecular substitutions have also been observed in 6-methyl-4-diloro-3-[N-(2-methoxyphenyliminomethyl)] (2H) benzopyran and 6-methyl-4-chloro-3-[N-(2-chlorophenyliminomethyl)]-(2H) benzopyran. The proposed fragmentation mechanisms have been supported by the accurate mass measurements and linked scan studies.

Electron impact induced cyclizations in 4‐chioro‐3‐(N‐aryliminomethyl) (2H) benzopyrans and benzothiopyrans

Chromone-3-ylmethyl aryl ethers with unsubstituted ortho-positions have been found to undergo a novel domino [1,3]-[1,3]-rearrangement to give 4′-hydroxyhomoisoflavones under thermal conditions whi...

An Unexpected Thermal [1,3]-[1,3]-para Rearrangement of Chromone-3-ylmethyl Aryl Ethers: Mechanism and Application of the Intercepted [1,3]-Rearranged Intermediates to the Synthesis of cis-Homopterocarpans

A facile atom economic and eco friendly protocol for the synthesis of biologically important quaternary centered C-3 functionalized oxindole derivatives, with a novel nucleus, in high yields has been demonstrated by employing 3-hydroxy-2-oxindole, isoxazolone/pyrazolone and environmentally benevolent p-toluene sulphonic acid as a catalyst. The advantages of this protocol are the wide substrate scope, practical simplicity, benign solvent and good yields. All the synthesized compounds were evaluated for their in vitro anti-microbial activity. Several compounds exhibited good activities comparable to those of established standard drugs. Furthermore, the anti-cancer activity of compounds 3g and 3m has been preliminarly demonstrated by in vitro evaluation against human tumor cell lines MCF-7 and Hep-2, using MTT-based assays with commercially available standard drug cisplatin as a positive control. Gratifyingly, compounds 3g and 3m exhibited good in vitro inhibitory activities against Hep-2 and MCF-7 cell lines. These results indicate that 3-indolyl oxindole substituted isoxazole analogs may be potential lead compounds for further biological screening.

Kalpattu K. Balasubramanian

Papers

On the claisen rearrangement of 1,4-diaryloxy-2-butynes

Radical Cyclisation of o-Haloaryl Allenylmethyl Ethers and Amines: Synthesis of 3-Ethenyl-2,3-dihydrobenzofurans and 3-Ethenyl-2,3-dihydroindoles

Electron impact induced cyclizations in 4‐chioro‐3‐(N‐aryliminomethyl) (2H) benzopyrans and benzothiopyrans

An Unexpected Thermal [1,3]-[1,3]-para Rearrangement of Chromone-3-ylmethyl Aryl Ethers: Mechanism and Application of the Intercepted [1,3]-Rearranged Intermediates to the Synthesis of cis-Homopterocarpans

Brønsted acid catalysed eco friendly synthesis of quaternary centred C-3 functionalized oxindole derivatives