Total synthesis of (+)-herboxidiene/GEX 1A

Gómez‐Palomino, Alejandro; Pellicena, Miquel; Krämer, Katrina; Romea, Pedro; Urpı́, Fèlix; Aullón, Gabriel; Padrón, José M.

doi:10.1039/c7ob00072c

Cited by 7 publications

(2 citation statements)

References 87 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Again in 2017 same group published a complete account of their synthetic accomplishments, including theoretical studies of hydroxy esters oxa‐Michael reaction used in their total synthesis . Authors also studied the biological activity of herboxidiene/GEX1A and its synthetic analogues against human tumor cell lines HBL‐100, HeLa, SW1573, T‐47D and WiDr to get structure–activity relationships . Authors verified some structural modification such, hydroxy protected ester which marked decrease in activity.…”

Section: Chemical Synthesesmentioning

confidence: 99%

Syntheses and Biological Importance of Herboxidiene/GEX1A

Thirupathi

Zilla

2019

ChemistrySelect

View full text Add to dashboard Cite

The importance of exceptionally potent bioactivities, scarcity of natural abundance and interesting structural features of herboxidiene/GEX1A attracted great interest from synthetic, medicinal chemists. In this review we discussed chemical syntheses and biological significances of herboxidiene/GEX1A. Aim of this review to gather valuable insights by various research groups into one place, to accelerate and design an efficient synthetic methods and surplus biological studies of herboxidiene/GEX1A. Existing reports are useful for design and develop new medications, reports includes: herbicidal activity, lowering of plasma cholesterol, anti‐tumor activity in numerous cell lines, pre‐mRNA splicing‐modulatory action, activity against Niemann‐Pick disease type C (NPC), and focuses on total syntheses of herboxidiene/GEX1A (Figure 1).

show abstract

Section: Chemical Synthesesmentioning

confidence: 99%

Syntheses and Biological Importance of Herboxidiene/GEX1A

Thirupathi

Zilla

2019

ChemistrySelect

View full text Add to dashboard Cite

show abstract

“…On the contrary, the base-mediated process delivers trans -2,6-THPs as kinetic products and proceeds via the cyclization of intermediate oxoanions. ,, The disadvantage of the strong base is epimerization of the kinetic trans -products into thermodynamically preferred cis -isomers, a process which is detrimental to attaining high trans -selectivity (Scheme b) . Although the isomerization process can be used for the preparation of cis -THPs, , the base-mediated reactions frequently suffer from poor diastereocontrol under both kinetic and thermodynamic conditions . Since separation of diastereomers is not always easy to perform, the development of an expedient stereodivergent protocol for the synthesis of cis - and trans -2,6-disubstituted THPs via the base-mediated oxa-Michael cyclization is still in demand.…”

Section: Introductionmentioning

confidence: 99%

Stereodivergent Assembly of 2,6-cis- and -trans-Tetrahydropyrans via Base-Mediated Oxa-Michael Cyclization: The Key Role of the TMEDA Additive

et al. 2022

View full text Add to dashboard Cite

The stereodivergent synthesis of cis- and trans-2,6-disubstituted tetrahydropyrans (THPs) via sodium hexamethyldisilazide-promoted oxa-Michael cyclization of (E)-ζ-hydroxy α,β-unsaturated esters is presented. The cyclization affords the kinetically favored trans-THPs with high stereoselectivity (dr up to 93:7) at a low temperature (−78 °C), while the room-temperature reaction does not produce the thermodynamically preferred cis-THPs as major products and occurs with poor stereocontrol. The addition of tetramethylethylenediamine (TMEDA) significantly improves the stereochemical outcome of the room-temperature cyclization and allows attaining high cis-selectivity (dr up to 99:1). The remarkable effect of TMEDA indicates that the sodium cation plays an important role in controlling the stereoselectivity of the thermodynamically driven process, that is, complexation of the cation with the cyclization products results in diminished selectivity. DFT calculations support this conclusion, indicating a greater difference in Gibbs energies of sodium-free cis- and trans-enolates compared to the respective sodium chelate complexes. The synthetic utility of the method has been demonstrated by the formal syntheses of (+)-Neopeltolide and (−)-Diospongin B and the total synthesis of (−)-Diospongin A.

show abstract

Organocascade Synthesis of Spiro[chroman‐3,2′‐indanedione] Scaffolds via [4+2] or [1+1+4] Cyclisation

et al. 2021

View full text Add to dashboard Cite

A simple and convenient protocol has been demonstrated for the construction of spiro[chroman‐3,2′‐indanedione] via Oxa‐Michael/Michael cascade reaction sequence using 2‐arylidene‐1,3‐indanedione and (E)‐2‐(2‐nitrovinyl)phenol. This [4+2] cyclisation protocol results in the generation of two stereocentres along with an all carbon quaternary centre in good to high chemical yields of upto 93 %. A triple cascade reaction approach was carried out for the construction of spiro[chroman‐3,2′‐indanedione] using [1+1+4] cyclisation protocol.

show abstract

Total synthesis of (+)-herboxidiene/GEX 1A

Cited by 7 publications

References 87 publications

Syntheses and Biological Importance of Herboxidiene/GEX1A

Syntheses and Biological Importance of Herboxidiene/GEX1A

Stereodivergent Assembly of 2,6-cis- and -trans-Tetrahydropyrans via Base-Mediated Oxa-Michael Cyclization: The Key Role of the TMEDA Additive

Organocascade Synthesis of Spiro[chroman‐3,2′‐indanedione] Scaffolds via [4+2] or [1+1+4] Cyclisation

Contact Info

Product

Resources

About