Results 71 to 80 of about 6,329 (228)

Stereoselective Synthesis of (-)-Spicigerolide [PDF]

, 2013
(-)-Spicigerolide was enantioselectively synthesized from a protected (S)-lactaldehyde. The synthesis of the polyacetylated framework relied on two Zn-mediated stereoselective additions of alkynes to aldehydes as well as a regiocontrolled [3,3 ...
Achmad S., Alemany A., Amador M., Anand N. K., Ariza X., Birch A. J., Boalino D. M., Boucard V., Boyal D., Boyer J., Collet L. A., Connon S. J., Davies-Coleman M. T., Davis-Coleman M. T., Diez R. S., Díaz-Oltra S., El-Sayed E., Falomir E., Falomir E., Frantz D. E., Fürstner A., Gao D., Gao D., García-Fortanet J., García-Fortanet J., Hafner A., Hoveyda A. H., Kojima N., Lichtenthaler F. W., Lichtenthaler F. W., Marco J. A., Murga J., Pereda-Miranda R., Pereda-Miranda R., Ramachandran P. V., Saito S., Trnka T., Trost B. M., Valverde S.   +38 more
core   +2 more sources

Re-investigation of the fragmentation of protonated carotenoids by ESI and nanoESI-CID-MS/MS [PDF]

, 2016
RATIONALE Carotenoids are polyene isoprenoids with an important role in photosynthesis and photoprotection. Their characterization in biological matrices is a crucial subject for biochemical research.
Carnevale Neto, Fausto, Colepicolo, Pio, Costa-Lotufo, Leticia, Gates, Paul, Guaratini, Thais, Peporine Lopes, Norberto   +5 more
core   +2 more sources

Enantioselective Synthesis of (+)-Cephalostatin 1 [PDF]

, 2012
This Article describes an enantioselective synthesis of cephalostatin 1. Key steps of this synthesis are a unique methyl group selective allylic oxidation, directed C−H hydroxylation of a sterol at C12, Au(I)-catalyzed 5-endo-dig cyclization, and a ...
Fortner, Kevin, Kato, Darryl, Shair, Matthew David, Tanaka, Yoshiki   +3 more
core   +1 more source

Effect of Ring Size and Migratory Groups on [1,n] Suprafacial Shift Reactions. Confirmation of Aromatic and Antiaromatic Transition-State Character by Ring-Current Analysis [PDF]

, 2016
Suprafacial sigmatropic shift reactions of 5-substituted cyclopentadienes, 3-substituted cyclopropenes, and 7-substituted cycloheptatrienes have been studied computationally at the MP2/6-31+G* level for structures and energetics, and using the ...
Clarke, J., Fowler, P.W., Gronert, S., Keeffe, J.R.   +3 more
core   +1 more source

A Minimal, Unstrained S-Allyl Handle for Pre-Targeting Diels-Alder Bioorthogonal Labeling in Live Cells [PDF]

, 2016
The unstrained S-allyl cysteine amino acid was site-specifically installed on apoptosis protein biomarkers and was further used as a chemical handle and ligation partner for 1,2,4,5-tetrazines by means of an inverse-electron-demand Diels-Alder reaction ...
,, Bernardes, GJL, Boutureira, O, Guerreiro, A, Guo, Z, Jiménez-Osés, G, Oliveira, BL   +6 more
core   +4 more sources

Synthesis of Fully Substituted Pyrimidines [PDF]

, 2016
A novel approach to the synthesis of fully substituted pyrimidine derivatives armed with an oxy-functionalized acetate chain at the ring is described. The manifold uses amidines as the nitrogen source and activated skipped diynes as the electrophilic
García-Tellado, Fernando, López-Tosco, Sara, Tejedor, David   +2 more
core   +2 more sources

Reaksi Penataan Ulang Sigmatropik Hidrogen [1,3] Secara Termal dan Reaksi Penataan Ulang Prototropik [1,3] yang dikatalisis oleh Katalis Transfer Fase (Ptc) , [18]-Crown Ether-6: Semi-Sintesis Vanili dari Eugenol

Makara Seri Sains, 2002
Semi-synthesis of vanillin from eugenol can be divided into two step reactions namely, isomerization of eugenol intoisoeugenol, and cleavage oxidation of isomerization product into expected reaction product (vanillin).
Hendra Wijaya, Tony Sukri, Wahyudi Priyono Suwarso   +2 more
doaj  

Reversal of facial selectivity in a thia-Claisen rearrangement by incorporation of a vinylic bromine substituent [PDF]

, 2013
Thia-Claisen rearrangements have been carried out using N-benzylpyrrolidine-2-thione and chiral allylic bromides derived from D-mannitol.
Ellwood, AR, Goodman, JM, Mortimer, AJP, Porter, MJ   +3 more
core   +1 more source

Cover Picture: Hemin Catalyzed Dealkylative Intercepted [2, 3]‐Sigmatropic Rearrangement Reactions of Sulfonium Ylides with 2, 2, 2‐Trifluorodiazoethane (Adv. Synth. Catal. 10/2020) [PDF]

, 2020
Xiaojing Yan, Chang Li, Xiaofei Xu, Xiaoyong Zhao, Yuanjiang Pan   +4 more
openalex   +1 more source

Tracking the Transition from Pericyclic to Pseudopericyclic Reaction Mechanisms Using Multicenter Electron Delocalization Analysis: The [1,3] Sigmatropic Rearrangement [PDF]

, 2021
Álvaro Pérez‐Barcia, Ángeles Peña‐Gallego, Marcos Mandado   +2 more
openalex   +1 more source