Synthesis of nonracemic hydroxyglutamic acids

• Dorota G. Piotrowska,
• Iwona E. Głowacka,
• Andrzej E. Wróblewski and
• Liwia Lubowiecka

Beilstein J. Org. Chem. 2019, 15, 236–255, doi:10.3762/bjoc.15.22

• acid [(2S,3S,4R)-4] was obtained as the hydrochloride. To avoid racemization at Cα in sensitive amino acids the carboxy group was frequently masked as an orthoester. To illustrate this strategy dihydroxylation of the orthoester 92 (derived from L-pyroglutamic acid [97]) was performed to afford a single

• /H2O; e) BnOH or p-MeO-C6H4-CH2OH, NaH, THF. Synthesis of the protected (4R)-4-hydroxy-L-pyroglutamic acid (2S,4R)-87 by electrophilic hydroxylation. Reagents and conditions: a) LiHMDS, THF, and then 3-phenyl-N-phenylsulfonyl oxaziridine. Synthesis of (2S,3S,4R)-4 from the epoxypyrrolidinone 88

Diastereoselective radical addition to γ-alkyl-α-methylene-γ-butyrolactams and the synthesis of a chiral pyroglutamic acid derivative

• Tomoko Yajima,
• Eriko Yoshida and
• Masako Hamano

Beilstein J. Org. Chem. 2013, 9, 1432–1436, doi:10.3762/bjoc.9.161

• synthesize chiral pyroglutamic acid derivatives starting from (S)-phenylglycinol. Chelation of 5a and 5d. Radical addition to α-methylene-γ-phenyl-γ-butyrolactams. Synthesis of chiral substrate 10. Synthesis of chiral 4-butyl-L-pyroglutamic acid 13. Radical addition to 1 under non-chelating conditions

A new approach toward the total synthesis of (+)-batzellaside B

• Jolanta Wierzejska,
• Shin-ichi Motogoe,
• Yuto Makino,
• Tetsuya Sengoku,
• Masaki Takahashi and
• Hidemi Yoda

Beilstein J. Org. Chem. 2012, 8, 1831–1838, doi:10.3762/bjoc.8.210

• (+)-batzellaside B from naturally abundant L-pyroglutamic acid is presented in this article. The key synthetic step involves Sharpless asymmetric dihydroxylation of an olefinic substrate functionalized with an acetoxy group to introduce two chiral centres diastereoselectively into the structure. Heterocyclic

• ; L-pyroglutamic acid; total synthesis; Introduction Iminosugars, monosaccharide analogues in which the endocyclic oxygen has been replaced by nitrogen, display beneficial therapeutic activity as sugar-mimicking glycosidase inhibitors [1][2][3][4]. Since the discovery of nojirimycin (Figure 1), which

• more efficient and convenient access to this natural product and its derivatives. From a retrosynthetic point of view, L-pyroglutamic acid, whose rich natural abundance makes it a commercially and economically viable substrate [21], can be envisaged as a potentially practical starting material for this

A convenient allylsilane- N-acyliminium route toward indolizidine and quinolizidine alkaloids

• Roland Remuson

Beilstein J. Org. Chem. 2007, 3, No. 32, doi:10.1186/1860-5397-3-32

• approach to 3,5-disubstituted indolizidines based on an intermolecular addition of allylsilanes on an N-acyl iminium starting from L-pyroglutamic acid used as the chiral precursor. Preparation of lactam 14 was accomplished starting from the commercially available S-(-)-pyroglutamic acid according to a

• cyclisation. Synthesis of (±)-indolizidine 167B by intermolecular cyclisation of allylsilane-N-acyliminium cyclisation. Synthesis of 3,5-disubstituted indolizidines from L-pyroglutamic acid. Access to indolizidine precursors of dendroprimine starting from chiral 2-aminopropanoate. Access to (-)-dendroprimine