Bis(ethylsulfonamide)amines via nucleophilic ring-opening of chiral aziridines. Application to Ti-mediated addition of diethylzinc to benzaldehyde

Cernerud, Magnus; Skrinning, A.; Bergere, Isabelle; Moberg, Christina

doi:10.1016/s0957-4166(97)00410-2

Cited by 39 publications

(20 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The route to fragment 4 commenced with the catalytic asymmetric cyclocondensation of 4-(benzyloxy)-1-butanal (13) [10] with acetyl bromide using triamine ligand 14 [11] by a modification of the procedure previously reported by Nelson et al (Scheme 3). [12] Dimethyl cuprate, generated in situ, was reacted with 15 to afford the corresponding acid, which was readily transformed into tert-butyl ester 16.…”

mentioning

confidence: 99%

Syntheses and Biological Evaluation of Iriomoteolide 3a and Analogues

2009

View full text Add to dashboard Cite

Amphidinium species are an extremely prolific source of marine secondary metabolites.[1] Structurally unique polyketides such as amphidinolides, caribenolide I, and amphidinolactones have fostered the interest of chemists not only as challenging targets for total synthesis but also because of their potent anticancer activity.[2] Recently, the Amphidinium strain HYA024 was found to produce cytotoxic compounds such as iriomoteolides 1a-c, [3] and a rare 15-membered macrolide, iriomoteolide 3a (1).[4] With a novel carbon framework comprising eight stereogenic centers, four of them in allylic positions, compound 1 represents the first member of a unique and unprecedented 15-membered macrolide class. Compound 1 represents the first member of a unique and unprecedented 15-membered macrolide class. In addition, the preliminary physiological properties disclosed for 1 and its 7,8-O-isopropylidene derivative 2 are very promising, showing potent cytotoxicity against lymphoma cell lines in the low nanomolar range. [4] To confirm the assigned structure, further evaluate its biological activity, and determine whether its cellular targets are related to those of larger congeners such as amphidinolides, [5] substantial quantities of these compounds are required. Our retrosynthetic approach to 1 involved four major disconnections, which revealed key fragments 3-6 as summarized in Scheme 1. Fragment 6 was planned to be incorporated at the end of our synthetic sequence by a JuliaKocienski olefination because of its widely recognized performance in the elaboration of such sensitive settings and also to ensure a flexible late-stage diversification of the parent compound. An intermolecular esterification was envisioned to assemble fragments 3 and 4. Finally, we hypothesized that the C 2 -symmetry of the diol precursor of fragment 5 could be advantageously used to construct the 1,5-diene upon ring closure by a cross-metathesis (CM)/ringclosing metathesis (RCM) approach. We were relying on the excellent results achieved by the Grubbs-type carbene complexes in both CM and RCM processes with the expectation that the formation of a medium-sized ring would also be E,E stereoselective (Scheme 1).The required building block 3 (Scheme 2) was prepared by alkylation of the Evans oxazolidinone 7[6] with iodide 8.[7]Scheme 2. a) Na[N( , THF, 73 %; n) DDQ, CH 2 Cl 2 , pH 7 buffer, RT, 85 %. CSA = camphorsulfonic acid, DDQ = 2,3-dichloro-5,6-dicyano-1,4-benzoquinone, DIBAL-H = diisobutylaluminium hydride, DIPT = diisopropyl tartrate, DMF = N,N-dimethylformamide, DMSO = dimethylsulfoxide, MS = molecular sieves, PMB = para-methoxybenzyl, PPTS = pyridinium para-toluenesulfonate, TBAF = tetra-n-butylammonium fluoride, TBDPS = tert-butyldiphenylsilyl, TBS = tert-butyldimethylsilyl.Scheme 1. Retrosynthetic analysis for iriomoteolide 3a (1).

show abstract

mentioning

confidence: 99%

Syntheses and Biological Evaluation of Iriomoteolide 3a and Analogues

2009

View full text Add to dashboard Cite

show abstract

“…[24,31] Alternatively, as was recently demonstrated, the formation of products from single or double ring-opening can be controlled by the choice of solvent. [32] The presently described compounds are expected to serve as useful ligands for metal ions and main group elements in catalytic applications.…”

Section: Resultsmentioning

confidence: 97%

A General Method for the Preparation of Chiral TREN Derivatives

et al. 2005

Self Cite

View full text Add to dashboard Cite

show abstract

“…with an aldehyde or a ketone [14]. The synthesis of the following ligands were carried out according to the literature procedures : L14 [15], L37 [16], L42, L45 [17], L43-L44 [18], L46 [19], L59 [20], L61, L84 [21], L65 [22], L76 [23], L77-L78 [24], L87-L88 [25], L91 [26], L92 [27], L93 [28], L94 [29], L95 [30], L100 [31], L101 [32]. Amino alcohols L68-L75 and diamine L79 were commercially available.…”

Section: Library Design and Presentationmentioning

confidence: 99%

High Throughput Screening and Evolution of a Library of Ligands in Asymmetric H-Transfer Reduction of Acetophenone

Abdallah¹,

Grenouillet²,

Vriamont³

et al. 2010

CCHTS

View full text Add to dashboard Cite

A library of 117 ligands was combined with three transition metals Ru, Rh and Ir and screened with three different operating conditions for the asymmetric H-transfer reduction of acetophenone into phenylethanol. The combinatorial approach was based on evolution of a first library containing 60 ligands. For the evolution, operators such as replication, regression, cross-over and mutation were used. The study was performed with a XYZ robot and fast chiral GC analysis. Over only 4 generations, the average targeted criterion, enantioselectivity, was increased from 20% to ca. 80% for the 4th generation. The best results provided enantiomeric excess up to 93%.

show abstract

Bis(ethylsulfonamide)amines via nucleophilic ring-opening of chiral aziridines. Application to Ti-mediated addition of diethylzinc to benzaldehyde

Cited by 39 publications

References 24 publications

Syntheses and Biological Evaluation of Iriomoteolide 3a and Analogues

Syntheses and Biological Evaluation of Iriomoteolide 3a and Analogues

A General Method for the Preparation of Chiral TREN Derivatives

High Throughput Screening and Evolution of a Library of Ligands in Asymmetric H-Transfer Reduction of Acetophenone

Contact Info

Product

Resources

About