Conversion of .beta.-hydroxyglutarohydroxamates to carbapenem precursors

Morrison, Marjorie A.; Miller, Marvin J.

doi:10.1021/jo00171a062

Cited by 20 publications

(2 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In fundamental research, efficient biomimetic methods for b-lactam syntheses were developed based on the intramolecular N-alkylation of b-hydroxyalkoxamates derived from amino acids. [42][43][44][45] In contrast, recent studies have revealed that competitive O-alkylation occurs in several cases with amides and carbamates. [46][47][48][49][50][51][52] We have therefore investigated the intramolecular cyclization of d-hydroxyalkoxamates derived from d-glycono-1,5-lactone under Mitsunobu conditions.…”

Section: Introductionmentioning

confidence: 99%

Divergent Synthesis of L‐Sugars and L‐Iminosugars from D‐Sugars

Takahashi

Shida

Hitomi

et al. 2006

Chemistry A European J

View full text Add to dashboard Cite

An efficient divergent synthesis of L-sugars and L-iminosugars from D-sugars is described. The important intermediate, delta-hydroxyalkoxamate, prepared from D-glucono-/galactono-1,5-lactone, was cyclized under Mitsunobu conditions to give the O-cyclized oxime compound and the N-cyclized lactam compound as mixtures. A more detailed investigation revealed that the appropriate protecting groups and solvents controlled the specificity for the O-/N-cyclization of the delta-hydroxyalkoxamate. Suitable protection at the 6-position of delta-hydroxyalkoxamate, derived from D-glucono-1,5-lactone, afforded the corresponding O-alkylation product alone. Thus we succeeded in applying this to the total synthesis of L-iduronic acid. In contrast, with both TBDMS as the protecting group and RCN as the solvent the efficient conversion of D-glucono/galactono-1,5-lactone into the corresponding L-iminosugars (L-idonolactam and L-altronolactam) was achieved.

show abstract

Section: Introductionmentioning

confidence: 99%

Divergent Synthesis of L‐Sugars and L‐Iminosugars from D‐Sugars

Takahashi

Shida

Hitomi

et al. 2006

Chemistry A European J

View full text Add to dashboard Cite

show abstract

“…Several methods for the synthesis of 3,4-disubstituted β-lactams are now available. In particular, the addition of imines to ketenes 4 or to ester enolates 5 has acquired significant importance for the asymmetric synthesis of the azetidinone ring. 1a, Alternatively, precursors from the “chiral pool” for the synthesis of β-lactams are, for example, β-amino acids, β-amino esters, β-halo amides, and β-hydroxy amides . However, methods for the construction of β-lactams with quaternary stereogenic centers are still scarce.…”

Section: Introductionmentioning

confidence: 99%

(3R)-Chiral Control of 3-Alkyl-3-hydroxy-β-lactams via Addition Reaction of Imines to Enolates of 1,3-Dioxolan-4-ones

et al. 1999

View full text Add to dashboard Cite

A method is described for the chiral construction of (3R)-3-alkyl-3-hydroxy-beta-lactams in a versatile and predictable manner. This protocol follows Seebach's synthetic principle of self-regeneration of stereocenters and has been applied to addition reactions among a selected number of imines and (2S)-chiral enolates of 1,3-dioxolan-4-ones. These reagents are easily available from the acetalization of (S)-alpha-hydroxy acids (lactic, mandelic, isovaleric, malic) and pivalaldehyde or pinacolone. In several cases, the addition of the enolate to the imine, the cyclization, and the removal of the auxiliary center occur in a one-step sequence, affording the corresponding beta-lactams as (3R,4S)-Z and (3R,4R)-E diastereomeric mixtures with high enantiomeric excesses. Four N-unsubstituted (3R,4S)-3-hydroxy-3-methyl-beta-lactams bearing 2-furyl (4e), phenylethenyl (4h), methoxycarbonyl (4i), and 2-thienyl (4l) substituents at C4 were obtained as major diastereomers and were purified by crystallization. The simultaneous presence of these substituents at C3 and C4 make these beta-lactams useful intermediates for the synthesis of new taxoids with interesting structural modifications at the isoserine moiety.

show abstract

TheMitsunobu Reaction

1992

View full text Add to dashboard Cite

Alkyl and aryl phosphites and phosphines react with compounds having weak heteroatom–heteroatom bonds, such as SS, OO, etc., and with azo compounds to form reactive phosphonium salts. These phosphonium salts in turn promote “redox” condensation reactions with compounds having active hydrogens. The condensation reaction of alcohols using the redox couple of a triaryl‐ or trialkylphosphine and a dialkyl azodicarboxylate has become known as the Mitsunobu reaction, based on his pioneering work in the late 1960s. The overall reaction is summarized, wherein the alcohol (R 1 OH) and acidic compound (H–Nu) are condensed to form product (R 1 –Nu), while triphenylphosphine is oxidized to triphenylphosphine oxide and the azodicarboxylate is reduced to the hydrazine. Although the typical redox combination is diethyl azodicarboxylate (DEAD) and triphenylphosphine, many other combinations have found selected use. The reaction is generally limited to primary and secondary alcohols, although tertiary alcohols react in a few intramolecular and intermolecular reactions. For secondary alcohols the reaction usually proceeds with clean inversion of stereochemistry. The acidic component of the reaction generally has an aqueous p K a < 15, with intramolecular reactions providing the exceptions. Examples of H–Nu include oxygen nucleophiles such as carboxylic acids and phenols; nitrogen nucleophiles such as imides, hydroxamates, and heterocycles; sulfur nucleophiles such as thiols and thioamides; and carbon nucleophiles such as β‐ketoesters. Major reviews of the Mitsunobu reaction were published in 1981 by Mitsunobu and in 1983 by Castro. The former review concentrated on reactions using DEAD/triphenylphosphine, while the latter review focused on reactions in which halogens replaced the hydroxy group using reagents such as triphenylphosphine/carbon tetrachloride, triphenyl phosphite/iodomethane, and triphenylphosphine/ N ‐halosuccinimide. Reactions involving the DEAD/triphenylphosphine redox system are the principal subject of this chapter, with emphasis on the literature between 1981 and 1988.

show abstract

Conversion of .beta.-hydroxyglutarohydroxamates to carbapenem precursors

Cited by 20 publications

References 5 publications

Divergent Synthesis of L‐Sugars and L‐Iminosugars from D‐Sugars

Divergent Synthesis of L‐Sugars and L‐Iminosugars from D‐Sugars

(3R)-Chiral Control of 3-Alkyl-3-hydroxy-β-lactams via Addition Reaction of Imines to Enolates of 1,3-Dioxolan-4-ones

TheMitsunobu Reaction

Contact Info

Product

Resources

About