@article { ISI:000232166800055, title = {Carbohydrate-based approach for the total synthesis of 1,3-polyol/alpha-pyrone antifungal natural products}, journal = {Journal of Organic Chemistry}, volume = {70}, number = {20}, year = {2005}, month = {SEP}, pages = {8216-8219}, publisher = {AMER CHEMICAL SOC}, type = {Article}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

An elimination and stereoselective hydrogenation of alpha-D-glucoheptonic-gamma-lactone derivative has been applied to prepare a differentially protected anti,anti-1,3,5-triol system, the utility of which has been extended for the total synthesis of anti-fungal 1,3-polyol/alpha-pyrone natural products.

}, issn = {0022-3263}, doi = {10.1021/jo050972v}, author = {Ramana, Chepuri V. and Srinivas, B. and Puranik, Vedavati G. and Gurjar, M. K.} } @article { ISI:000284515800005, title = {Combined experimental and density functional theory study on the Pd-mediated cycloisomerization of o-alkynylnitrobenzenes - synthesis of isatogens and their evaluation as modulators of ROS-mediated cell death}, journal = {European Journal of Organic Chemistry}, number = {31}, year = {2010}, month = {NOV}, pages = {5955-5966}, publisher = {WILEY-V C H VERLAG GMBH}, address = {PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY}, abstract = {

Highly selective cycloisomerization of o-alkynylnitrobenzenes, leading to isatogens, has been achieved by employment of a Pd-II complex. This reaction is very general and functional-group-tolerant. The possible mechanism of this reaction was investigated with the help of DFT calculations. Three possible pathways - namely, the addition of the nitro group either in (i) 5-exo-dig or (ii) 6-endo-dig mode and (iii) halopalladation - and subsequent intramolecular events have been considered and studied in detail. These investigations revealed that pathway (i) is the favored route to isatogen formation. A preliminary screening of the available isatogens reveals the 2-alkylisatogens to be novel ROS scavengers capable of inhibiting cellular necroptosis.

}, keywords = {Anthranil, cyclization, Density functional calculations, isatogens, Nitro-alkyne cycloisomerization, Palladium}, issn = {1434-193X}, doi = {10.1002/ejoc.201000769}, author = {Ramana, Chepuri V. and Patel, Pitambar and Vanka, Kumar and Miao, Benchun and Degterev, Alexei} } @article { ISI:000366864700006, title = {Cu-catalyzed sequential C-N bond formations: expeditious synthesis of tetracyclic indoloindol-3-ones}, journal = {Organic Chemistry Frontiers}, volume = {3}, number = {1}, year = {2016}, month = {NOV}, pages = {43-46}, publisher = {CHINESE CHEMICAL SOC}, address = {PO BOX 1-18, NANKANG, TAIPEI 115, TAIWAN}, abstract = {

The tetracyclic indoloindol-3-one core has been forged from easily accessible 2,2{\textquoteright}-bis-bromochalcones employing a reaction cascade comprising Cu-catalyzed SNAr with azide; nitrene C-H insertion and intramolecular Ullmann reaction with all three C-N bond formations in one-go.

}, issn = {2052-4129}, doi = {10.1039/c5qo00248f}, author = {Kulkarni, Anand M. and Srinivas, Kolluru and Deshpande, Mukund V. and Ramana, Chepuri V.} } @article {43165, title = {Concise approach for central core of trigolutes: total synthesis of trigolute B and 3-epi-trigolute B and analogues}, journal = {Tetrahedron}, volume = {73}, year = {2017}, month = {FEB}, pages = {888 - 899}, abstract = {

A concise approach comprising a combination of the Pd- or Ir-catalyzed Tsuji-Trost allylation and olefin dihydrox-ylation/acid catalyzed lactonization has been developed to construct the central spirolactone core of trigolutes with the requisite functional groups. A large number of analogues of trigolute B have been synthesized. Furthermore, the synthesis of both ({\textpm})-trigolute B and ({\textpm})-3-epi-trigolute B has been accomplished in 4{\textendash}5 steps from easily accessible building blocks.

}, author = {Reddy, B. Narendraprasad and Ramana, Chepuri V.} } @article {48730, title = {Concise approach for the synthesis of the tetracyclic framework of Lycibarbarines A and B}, journal = {Tetrahedron Letters}, volume = {121}, year = {2023}, month = {MAY }, type = {Article}, abstract = {

A simple approach for the construction of the tetracyclic spiroketal skeleton of Lycibarbarine A and B has been described. Employing a solvent free condition for epoxide opening with tetrahydroquinoline as a key reaction to couple both the fragments, an oxidation followed by TBAF-mediated silyl deprotection spiroketalization establishes the complete tetracyclic core present in these natural products. (c) 2023 Elsevier Ltd. All rights reserved.

}, keywords = {Chiral pool approach, D -Glyceraldehyde, Tetracyclic spiroketal, Total synthesis}, issn = {0040-4039}, doi = {10.1016/j.tetlet.2023.154493}, author = {Shet, Manoj N. and Nechooli, Hemanth K. and Ramana, Chepuri V.} }