Fluorine effect in nucleophilic fluorination at C4 of 1,6-anhydro-2,3-dideoxy-2,3-difluoro-β-D-hexopyranose

• Danny Lainé,
• Vincent Denavit,
• Olivier Lessard,
• Laurie Carrier,
• Charles-Émile Fecteau,
• Paul A. Johnson and
• Denis Giguère

Beilstein J. Org. Chem. 2020, 16, 2880–2887, doi:10.3762/bjoc.16.237

• progress to the development of innovative synthetic methodology to access polyfluorosugars [18]. For our part, we recently described the preparation of multi-vicinal trifluorinated hexopyranose analogues 6–9 using the Chiron approach from levoglucosan (1, Figure 1) [19]. Various 1,6-anhydro-2,3-dideoxy-2,3

A carbohydrate approach for the formal total synthesis of (−)-aspergillide C

• Pabbaraja Srihari,
• Namballa Hari Krishna,
• Ydhyam Sridhar and
• Ahmed Kamal

Beilstein J. Org. Chem. 2014, 10, 3122–3126, doi:10.3762/bjoc.10.329

• , utilizing a Trost hydrosilylation and protodesilylation as key reactions. Keywords: alkynylation; chiron approach; Ferrier-type C-glycosylation; macrolide; Introduction Aspergillides A, B and C (Figure 1) (three, novel, bicyclic, 14-membered macrolides with 2,6-cis or trans-fused di- or tetrahydropyan

• approach has been a conventional strategy to achieve the total synthesis of complex, natural products with known handedness. Herein we disclose our strategy for the formal total synthesis of (−)-aspergillide C in a concise manner following the chiron approach. Retrosynthetic Analysis Through a

• present context, we have focused on a chiron approach for the synthesis of aspergillide C and thus chose commercially available tri-O-acetyl-D-galactal as the raw material, which can be directly utilized for the synthesis of the dihydropyran motif. The side arm fragment 10 was readily available in large

Synthesis of (2S,3R)-3-amino-2-hydroxydecanoic acid and its enantiomer: a non-proteinogenic amino acid segment of the linear pentapeptide microginin

• Rajendra S. Rohokale and
• Dilip D. Dhavale

Beilstein J. Org. Chem. 2014, 10, 667–671, doi:10.3762/bjoc.10.59

• -hydroxy-β-aminodecanoic acid (AHDA, 2a) and its enantiomer 2b. The enantiomer of 2a is the N-terminal part of the natural linear pentapeptide microginin, which is used as an antihypertensive agent. Keywords: AHDA; carbohydrate; chiron approach; enantioselective; natural products; non-proteinogenic amino

A versatile and efficient approach for the synthesis of chiral 1,3-nitroamines and 1,3-diamines via conjugate addition to new (S,E)-γ-aminated nitroalkenes derived from L-α-amino acids

• Vera Lúcia Patrocinio Pereira,
• André Luiz da Silva Moura,
• Daniel Pais Pires Vieira,
• Leandro Lara de Carvalho,
• Eliz Regina Bueno Torres and
• Jeronimo da Silva Costa

Beilstein J. Org. Chem. 2013, 9, 832–837, doi:10.3762/bjoc.9.95

• combinations of both [42][43][44]. Nonetheless, the use of chiral nitroalkenes bearing a stereogenic center in the γ-position in nonracemic diastereoselective syntheses ("chiron" approach [45]) is less frequent in the literature. Notably, chiral nitroalkenes derived from carbohydrates [46][47][48][49][50] have

• enantioselective synthesis as chiral auxiliaries, chiral catalysts, chiral reagents and chiral ligands [59][60]. In our continuing interest in synthesizing new chiral nonracemic nitro compounds [61][62][63][64][65][66][67][68] by a "chiron" approach [45], we intended to develop a route for obtaining γ-nitrogenated

Recent progress on the total synthesis of acetogenins from Annonaceae

• Nianguang Li,
• Zhihao Shi,
• Yuping Tang,
• Jianwei Chen and
• Xiang Li

Beilstein J. Org. Chem. 2008, 4, No. 48, doi:10.3762/bjoc.4.48

• remained unknown. In 1998, Hanessian’s group [28] reported the stereocontrolled first total synthesis of a diastereomer of the presumed mono-THF type acetogenin annonacin A utilizing the “Chiron approach” (Scheme 4). The well-known lactone 30 obtained from L-glutamic acid was elaborated to a lactone