@article { ISI:000229376400004, title = {Simple synthesis of (+/-)-sarkomycin}, journal = {Synthesis-Stuttgart}, number = {8}, year = {2005}, month = {MAY}, pages = {1234-1236}, publisher = {GEORG THIEME VERLAG KG}, type = {Article}, address = {RUDIGERSTR 14, D-70469 STUTTGART, GERMANY}, abstract = {

A facile 6-step route to (+/-)-sarkomycin in 17\% overall yield has been described via Michael addition of nitromethane to 2-hydroxymethyl-2-cyclopentenone, oxone-induced oxidative Nef reaction, and acid catalyzed dehydration.

}, keywords = {(+/-)-sarkomycin synthesis, 2-hydroxymethyl-2-cyclopentenone, Michael addition, nitromethane., oxidative Nef reaction, Oxone}, issn = {0039-7881}, doi = {10.1055/s-2005-861877}, author = {Kar, Anirban and N. P. Argade} } @article { ISI:000229484400013, title = {Synthesis of naturally occurring bioactive butyrolactones: maculalactones A-C and nostoclide I}, journal = {Tetrahedron}, volume = {61}, number = {22}, year = {2005}, month = {MAY}, pages = {5297-5302}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, type = {Article}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

Starting from citraconic anhydride (13), a simple multistep (9-10 steps) synthesis of naturally occurring butyrolactones maculalactone A (3), maculalactone B (1), maculalactone C (2) and nostoclide 1 (4) have been described with good overall yields via dibenzylmaleic anhydride (20) and benzylisopropylmaleic anhydride (27). The two anhydrides 20 and 27 were prepared by S(N)2{\textquoteright} coupling reactions of appropriate Grignard reagents with dimethyl bromomethylfumarate (14), LiOH-induced hydrolysis of esters to acids, bromination of carbon-carbon double bond, in situ dehydration followed by dehydrobromination and chemoselective allylic substitution of bromoatom in disubstituted anhydrides 19 and 26 with appropriate Grignard reagents. The NaBH4 reduction of these anhydrides 20 and 27 furnished the desired lactones 21 and 29, respectively. The lactone 21 on Knoevenagel condensation with benzaldehyde, furnished maculalactone B (1), which on isomerization gave maculalactone C (2). Selective catalytic hydrogenation of 1 gave maculalactone A (3). The conversion of lactone 29 to nostoclide 1 (4) is known. (c) 2005 Elsevier Ltd. All rights reserved.

}, keywords = {dimethyl bromomethylfumarate, disubstituted maleic anhydrides, maculalactone A-C, NaBH4 reductions, nostoclide 1, S(N)2 {\textquoteleft} Grignard couplings, synthesis}, issn = {0040-4020}, doi = {10.1016/j.tet.2005.03.065}, author = {Kar, Anirban and Gogoi, Sanjib and N. P. Argade} } @article {42600, title = {Synthesis of natural fimbrolides}, journal = {Synthesis-Stuttgart}, year = {2007}, month = {JUL}, pages = {2198-2202}, doi = {10.1055/s-2007-983755}, author = {Haval, Kishan P. and N. P. Argade} } @article { ISI:000252640600002, title = {Synthesis of gymnoascolide A}, journal = {Synthesis-Stuttgart}, number = {1}, year = {2008}, month = {JAN}, pages = {26-28}, publisher = {GEORG THIEME VERLAG KG}, type = {Article}, address = {RUDIGERSTR 14, D-70469 STUTTGART, GERMANY}, abstract = {

Recently isolated 4-benzyl-3-phenylfuran-2,5-dione and antifungal gymnoascolide A have been synthesized using the chemoselective S(N)2{\textquoteright} coupling of phenylmagnesium bromide with dimethyl 2-(bromomethyl)fumarate, chemoselective allylic substitution of bromide in 3-(bromomethyl)-4-phenylfuran-2,5-dione with phenylmagnesium bromide and regioselective N-Selectride-induced reduction of 3-benzyl-4-phenylfuran-2,5-dione as the key reactions.

}, keywords = {dimethyl (bromomethyl)fumarate, functionalized maleic anhydrides, gymnoascolide A, regioselective reduction, S(N)2 {\textquoteleft} Grignard coupling reaction}, issn = {0039-7881}, doi = {10.1055/s-2007-990901}, author = {Baag, Md. Merajuddin and N. P. Argade} } @article { ISI:000256231200018, title = {Synthesis of norpandamarilactonines, pandamarilactonines, and pandanamine}, journal = {Synthesis-Stuttgart}, number = {9}, year = {2008}, month = {MAY}, pages = {1455-1459}, publisher = {GEORG THIEME VERLAG KG}, type = {Article}, address = {RUDIGERSTR 14, D-70469 STUTTGART, GERMANY}, abstract = {

A facile route to naturally occurring (+/-)-norpandamarilactonines A and B, (+/-)-pandamarilactonines A-D, and pandanamine has been described from 3-methylfuran-2(5H)-one, with a reductive intramolecular aza-Michael-type addition as the key step.

}, keywords = {3-methylfuran-2(5H)-one, condensation, intramolecular aza-Michael reaction, pandamarilactonines}, issn = {0039-7881}, doi = {10.1055/s-2008-1072534}, author = {Gogoi, Sanjib and N. P. Argade} } @article { ISI:000264648900011, title = {Stereoselective synthesis of (+)-isoindolo-beta-carboline}, journal = {Tetrahedron-Asymmetry}, volume = {20}, number = {2}, year = {2009}, month = {FEB}, pages = {220-224}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

Starting from homophthalic anhydride and (S)-tryptophan, the stereoselective synthesis of (+)-isoindolo-beta-carboline has been described via the corresponding homophthalimide, its chemoselective oxidative ring contraction, and the intramolecular dehydrative ring closure followed by a geometry-specific demethoxycarbonylation. (C) 2009 Elsevier Ltd. All rights reserved.

}, issn = {0957-4166}, doi = {10.1016/j.tetasy.2009.01.001}, author = {Wakchaure, Prasad B. and Puranik, Vedavati G. and N. P. Argade} } @article { ISI:000266382800011, title = {Synthesis of the reported protoberberine gusanlung D}, journal = {Synthesis-Stuttgart}, number = {10}, year = {2009}, month = {MAY}, pages = {1667-1672}, publisher = {GEORG THIEME VERLAG KG}, address = {RUDIGERSTR 14, D-70469 STUTTGART, GERMANY}, abstract = {

Starting from homopiperonylamine or phenethylamine with homophthalic anhydride or 3,4-methylenedioxyhomophthalic acid, respectively, facile syntheses of the reported structures of (+/-)-gusanlung D and (+/-)-isogusanlung d were accomplished via regioselective reductive dehydration of the corresponding homophthalimides followed by an intramolecular acid-catalyzed or radical cyclization pathway. Starting from the corresponding suitably ortho-halogenated homophthalimides, the syntheses of dehydrogusanlung and dehydroisogusanhing D were completed via regioselective reductive dehydration followed by an intramolecular Heck coupling reaction as the key steps. The analytical and spectral data obtained for all four synthetic compounds differed from the reported data for natural gusanling D, and therefore the structural assignment of the natural product needs to be revised.

}, keywords = {gusanlung D, Heck reaction, homophthalic anhydride, homopiperonyl amine, reductive dehydration}, issn = {0039-7881}, doi = {10.1055/s-0028-1088050}, author = {Wakchaure, Prasad B. and Easwar, Srinivasan and N. P. Argade} } @article { ISI:000298827600079, title = {Sonogashira coupling reactions of bromomaleimides: route to alkyne/cis-Alkene/Alkyl maleimides: synthesis of luffarin X and cacospongionolide C}, journal = {Journal of Organic Chemistry}, volume = {77}, number = {1}, year = {2012}, month = {JAN}, pages = {739-746}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

Palladium-catalyzed Sonogashira coupling reaction of bromomaleimides with a diverse range of terminal alkynes has been demonstrated to furnish the corresponding alkynylmaleimides in very good yields. This coupling reaction followed by selective reduction of the triple bond to single bond have been utilized as the decisive steps to accomplish the first total synthesis of natural products (+/-)-luffarin X and (+/-)-cacospongionolide C.

}, issn = {0022-3263}, doi = {10.1021/jo2021218}, author = {Deore, Prashant S. and N. P. Argade} } @article { ISI:000312003800010, title = {Synthetic studies towards NG-121: diastereoselective synthesis of NG-121 methyl ether}, journal = {Synthesis-Stuttgart}, volume = {44}, number = {24}, year = {2012}, month = {DEC}, pages = {3797-3804}, publisher = {GEORG THIEME VERLAG KG}, address = {RUDIGERSTR 14, D-70469 STUTTGART, GERMANY}, abstract = {

Starting from unsymmetrically O-protected methyl 4-bromo-3,5-dihydroxybenzoate, a facile synthesis of the methyl ether of bioactive natural product NG-121 was accomplished in very good overall yield. The key steps were: Stille coupling reaction of the farnesyl unit with the electron-rich phenolic segment; hydroxy-directed selective epoxidation of the farnesyl chain along with concomitant phenol-driven intramolecular regio- and diastereoselective ring closure to the corresponding hydroxybenzopyran; and regioselective formylation followed by in situ reductive lactonization.

}, keywords = {4-bromo-3, 5-dihydroxybenzoate, formylation, intramolecular cyclization, lactonization, NG-121 methyl ether, Stille coupling}, issn = {0039-7881}, doi = {10.1055/s-0032-1317544}, author = {Singh, Mandeep and N. P. Argade} } @article { ISI:000341070100010, title = {Synthesis of chenopanone}, journal = {Indian Journal of Chemistry Section B-Organic Chemistry Including Medicinal Chemistry}, volume = {53}, number = {8}, year = {2014}, month = {AUG}, pages = {1140-1142}, publisher = {COUNCIL SCIENTIFIC \& INDUSTRIAL RES}, address = {ANUSANDHAN BHAWAN, 2 RAFI MARG, NEW DELHI, 110001, INDIA}, abstract = {

Starting from glyoxalic acid, a facile three step approach to chenopanone has been described utilizing the Barbier reaction as a key step.

}, keywords = {acid hydrolysis, Barbier reaction, chenopanone, condensation, Glyoxalic acid, isovaleraldehyde, synthesis}, issn = {0376-4699}, author = {Deore, Prashant S. and N. P. Argade} } @article { ISI:000342568800011, title = {Synthesis of (+)-harmicine}, journal = {Synthesis-Stuttgart}, volume = {46}, number = {19}, year = {2014}, month = {OCT}, pages = {2591-2594}, publisher = {GEORG THIEME VERLAG KG}, address = {RUDIGERSTR 14, D-70469 STUTTGART, GERMANY}, abstract = {

A facile convergent access to the important indole alkaloid (+)-harmicine is described, starting from tryptamine and (R)-acetoxysuccinic anhydride via the corresponding acetoxysuccinimide in very good overall yield. Regioselective reduction of an unsymmetrical imide carbonyl group and acid-catalyzed stereoselective intramolecular cyclization were the key features involved. The directing group to induce asymmetry was finally detached via the corresponding iodide by using tributyltin hydride chemistry.

}, keywords = {alkaloids, cyclization, imides, reduction, stereoselective synthesis}, issn = {0039-7881}, doi = {10.1055/s-0034-1378381}, author = {Mondal, Pravat and N. P. Argade} } @article { ISI:000360095900016, title = {Sulfuryl chloride promoted gem-dichlorination-dehydrochlorination in alkyl benzothiazinylacetates: synthesis of the skeleton of trichochrome pigments}, journal = {Synthesis-Stuttgart}, volume = {47}, number = {17}, year = {2015}, month = {SEP}, pages = {2631-2634}, publisher = {GEORG THIEME VERLAG KG}, address = {RUDIGERSTR 14, D-70469 STUTTGART, GERMANY}, abstract = {

Chemo- and stereoselective total synthesis of the basic trichochrome skeleton is described starting from o-aminothiophenol and maleic anhydride in very good overall yield. The process involves the synthesis of the corresponding 1,4-benzothiazin-2-ylacetates followed by their sulfuryl chloride induced dihalogenation-dehydrohalogenation and a second condensation with o-aminothiophenol as key steps.

}, keywords = {condensations, halogenation, maleic anhydride, o-aminothiophenol, trichochrome framework}, issn = {0039-7881}, doi = {10.1055/s-0034-1378714}, author = {Jangir, Ravi and Gadre, Smita R. and N. P. Argade} } @article { ISI:000350219700005, title = {Synthesis of yangjinhualine A}, journal = {Synthesis-Stuttgart}, volume = {47}, number = {4}, year = {2015}, month = {FEB}, pages = {485-488}, publisher = {GEORG THIEME VERLAG KG}, address = {RUDIGERSTR 14, D-70469 STUTTGART, GERMANY}, abstract = {

Selective reduction of 3-(4-hydroxyphenyl)-2-methylmaleic anhydride provides access the corresponding gamma-hydroxybutenolide natural product yangjinhualine A.

}, keywords = {anhydrides, lactones, Natural products, reduction, Regioselectivity}, issn = {0039-7881}, doi = {10.1055/s-0034-1379582}, author = {Deore, Prashant S. and Batwal, Ramesh U. and N. P. Argade} } @article {43626, title = {Stereoselective synthesis of (-)-desethyleburnamonine, (-)-vindeburnol and (-)-3-epitacamonine: observation of a substrate dependent diastereoselectivity reversal of an aldol reaction}, journal = {Organic \& Biomolecular Chemistry}, volume = {14}, year = {2016}, month = {OCT}, pages = {10394-10406}, abstract = {Starting from (-)-acetoxyglutarimide, the enantioselective multistep synthesis of (-)-desethyleburnamonine, (-)-vindeburnol and (-)-3-epitacamonine has been demonstrated via a common hydroxyl-lactam intermediate with very good overall yields. The acetoxy function from (-)-acetoxyglutarimide was initially used as a handle to induce enantioselectivity and then as a latent source of the ketone carbonyl group. Most importantly, substrate dependent reversal of the diastereoselectivity in ester aldol reactions of hexahydroindolo[2,3-a] quinolizinones has been reported.}, doi = {10.1039/c6ob01438k}, author = {Mondal, Pravat and N. P. Argade} } @article {42572, title = {Synthesis of (-)-phaitanthrin D and (+)-dihydropyrroloindoloquinazolinone}, journal = {Synthesis-Stuttgart}, volume = {48}, year = {2016}, month = {SEP}, pages = {2896-2903}, abstract = {

The synthesis of (-)-phaitanthrin D and (+)-dihydropyrroloindoloquinazolinone are reported starting from the corresponding especially designed enantiomerically pure pivotal anthranilamide based building blocks using HMDS/ZnCl2 and NaHMDS.

}, doi = {10.1055/s-0035-1562098}, author = {Vaidya, Sagar D. and N. P. Argade} } @article {44226, title = {Solid state auto-inversion of C-centrochirality: enantioselective total synthesis of furocarbazolones (-)-epi-claulansine D and (-)-claulansine D and pyranocarbazolone (+)-epi-claulansine C}, journal = {Journal of Organic Chemistry}, volume = {83}, year = {2018}, month = {JAN}, pages = {382-387}, type = {Article}, abstract = {

Starting from dimethyl (E)-2-{[(1-tert-butoxycarbonyl)-1H-indol-3-yl]methylene}succinate and (R)-2,2,5,5-tetramethyl-1,3-dioxolane-4-carbaldehyde, facile synthesis of (-)-epi-claulansine D was accomplished via condensation and two intramolecular cyclizations. The (-)-epi-claulansine D in the solid state exists in a metastable form, and after an induction period of 30-90 days, it underwent complete epimerization to exclusively deliver the desired natural product (-)-claulansine D in quantitative yield. The witnessed inversion of C-centrochirality in the solid state is conceptually novel and takes place for relatively higher crystal stability reasons. Base-catalyzed ring expansion of both (+/-)/(-)-epi-claulansine D and (+/-)/(-)-claulansine D resulted in (+/-)/(+)-epi-claulansine C in very good yields.

}, issn = {0022-3263}, doi = {10.1021/acs.joc.7b02773}, author = {Markad, Shivaji B. and N. P. Argade} }