@article { ISI:000263152800005, title = {Formal synthesis of (+)-didemniserinolipid B employing a Pd-mediated 6-endo selective alkynediol cycloisomerization}, journal = {Tetrahedron Letters}, volume = {50}, number = {3}, year = {2009}, month = {JAN}, pages = {271-273}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

Herein, we describe a concise assembly of central 6,8-dioxabicyclo[3,2,1]octane core of didemniserino-lipid by employing a Pd-mediated alkynediol cycloisomerization and a formal total synthesis of didemniserinolipid (C) 2008 Elsevier Ltd. All rights reserved.

}, keywords = {Alkynol cycloisomerization, Bridged bicyclic ketal, Didemniserinolipid, Yamaguchi oxirane alkyne coupling, Zipper reaction}, issn = {0040-4039}, doi = {10.1016/j.tetlet.2008.10.137}, author = {Ramana, C. V. and Induvadana, Boddeti} } @article { ISI:000315321400011, title = {Metal-mediated alkynediol cycloisomerization: first and second generation formal total syntheses of didemniserinolipid B}, journal = {Tetrahedron}, volume = {69}, number = {7}, year = {2013}, month = {FEB}, pages = {1881-1896}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

A formal total synthesis of didemniserinolipid B was developed by employing a regioselective metal-mediated 6-endo-dig alkynol-cycloisomerization reaction. Two routes for the synthesis of key Burke{\textquoteright}s intermediate have been developed. Our initial approach involved the introduction of a C-17-allcynol followed by Pd-mediated cycloisomerization and then coupling with the serinol unit prior to the introduction of an alpha,beta-unsaturated ester unit through selective oxidation of 1 degrees-OH followed by a two-carbon Wittig homologation. Alternatively, the second generation strategy featuring the serinol coupling with the C-17-alkynol followed by alkyne addition to the epoxide and subsequent Au-mediated cycloisomerization of an acetonide protected alkynediol unit has been executed. This approach has avoided several late stage protection-deprotection events. (C) 2012 Elsevier Ltd. All rights reserved.

}, keywords = {Alkynol-cycloisomerization, Bicyclic ketal, Gold catalysis, Palladium catalysis, Zipper reaction}, issn = {0040-4020}, doi = {10.1016/j.tet.2012.12.045}, author = {Das, Shyamsundar and Induvadana, Boddeti and Ramana, C. V.} } @article {49484, title = {Design and synthesis of C-α-D-mannopyranoside linked mesoporous silica nanoparticles}, journal = {Journal of Chemical Sciences}, volume = {137}, year = {2025}, month = {MAR }, pages = {21}, type = {Article}, abstract = {

Mannose functionalized mesoporous silica nanoparticles (MSNs) offer a promising approach for developing more targeted, effective, and safer cancer therapies. For many of the applications, immobilization of carbohydrates like mannose onto MSNs is a crucial aspect, and in most cases, mannose moieties are connected through O-glycosidic linkages that are susceptible to acidic/enzymatic hydrolysis. To generate a stable mannose-functionalized MSN, we designed a novel C(14)-alpha-mannosylated tetradeca-1-yne. The key steps involved in the synthesis of C-mannosylated alkyne are C1-alkynylation of tri-O-acetyl-D-glucal with 1-trimethylsilyl-tetradec-1-yne, followed by stereoselective dihydroxylation and the isomerization of the internal triple bond to a terminal position. This mannose ligand was then immobilized onto azidopropyl-functionalized SBA-15 through the Cu(I)-catalyzed azide-alkyne click (CuAAC) reaction. Various physical techniques such as low-angle powder XRD, N-2 adsorption isotherms (BET), Fourier transform infrared (FTIR), high-resolution transmission electron microscopy (HRTEM), field emission scanning electron microscopy (FE-SEM), and thermogravimetric analysis (TGA) have been employed to characterize this C-mannosyl SBA-15 silica matrix. We evaluated the binding ability of C-mannosyl SBA-15 nanoparticles by using fluorescein-labelled Con-A as a target protein.

}, keywords = {C-mannoside, Click reaction, mannose specific proteins, Mesoporous silica nanoparticles, Zipper reaction}, issn = {0974-3626}, doi = {10.1007/s12039-024-02338-7}, author = {Nechooli, Hemanth K. and Ramtenki, Vilas and Kumar, Chepuri V. Suneel and Prasad, V. B. L. and Ramana, V. Chepuri} }