Synthesis of ether lipids: natural compounds and analogues

• Marco Antônio G. B. Gomes,
• Alicia Bauduin,
• Chloé Le Roux,
• Romain Fouinneteau,
• Wilfried Berthe,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96

• 90% yield. In 1982, G. Hirth and R. Barner reported the synthesis of the two enantiomers of PAF [71]. The synthesis started from ᴅ-mannitol (4.1, Figure 4A). First, 4.1 was transformed to 1,2-isopropylidene-sn-glycerol (4.4) following a three-step sequence (45% yield over three steps) initially

• alcohol functions of 4.5 were deprotected in acidic media to produce 3-O-octadecyl-sn-glycerol (4.6). The enantiomer of 4.6 was obtained from 4.4 by protecting the primary alcohol with a benzyl group to give 4.7. Then, the deprotection of the two alcohol functions with H2SO4 in water followed by the

• hydrogenolysis to produce 1-O-octadecyl-sn-glycerol (4.10). It must be noted that the authors, after the deprotection of the two alcohol functions of 4.7, attempted the direct alkylation of the primary alcohol with octadecyltosylate. However, a mixture of mono and dialkylation was formed and were separated by

Nostochopcerol, a new antibacterial monoacylglycerol from the edible cyanobacterium Nostochopsis lobatus

• Naoya Oku,
• Saki Hayashi,
• Yuji Yamaguchi,
• Hiroyuki Takenaka and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2023, 19, 133–138, doi:10.3762/bjoc.19.13

• , Japan 10.3762/bjoc.19.13 Abstract A new antibacterial 3-monoacyl-sn-glycerol, nostochopcerol (1), was isolated from a cultured algal mass of the edible cyanobacterium Nostochopsis lobatus MAC0804NAN. The structure of compound 1 was established by the analysis of NMR and MS data while its chirality was

• esterification. The resulting ester 2a or 2b was purified by reversed-phase HPLC and deprotected by a short treatment with 80% aqueous acetic acid at 58–59 °C to give 1-linoleoyl-sn-glycerol (3a) or 3-linoleoyl-sn-glycerol (3b), respectively (Scheme 1). Similarly, to our experience during the isolation of

• and the concentration at which the growth of microbes was completely inhibited was defined as the minimum inhibitory concentration (MIC). Structure of nostochopcerol (1) and selected COSY (bold lines) and HMBC (arrows) correlations. Synthesis of 1-linoleoyl-sn-glycerol (3a) and 3-linoleoyl-sn-glycerol

Remarkable functions of sn-3 hydroxy and phosphocholine groups in 1,2-diacyl-sn-glycerolipids to induce clockwise (+)-helicity around the 1,2-diacyl moiety: Evidence from conformation analysis by ¹H NMR spectroscopy

• Yoshihiro Nishida,
• Mengfei Yuan,
• Kazuo Fukuda,
• Kaito Fujisawa,
• Hirofumi Dohi and
• Hirotaka Uzawa

Beilstein J. Org. Chem. 2017, 13, 1999–2009, doi:10.3762/bjoc.13.196

• of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba 305-8565, Japan 10.3762/bjoc.13.196 Abstract Cell-membrane glycerolipids exhibit a common structural backbone of asymmetric 1,2-diacyl-sn-glycerol bearing polar head groups in the sn-3 position. In this study, the possible

• ; deuterium labeling; sn-glycerol; glycerolipids; glycerophospholipids; helicity; Karplus equation; proton NMR spectroscopy; staggered conformers; Introduction Glycerophospholipids, constituting the basic elements of cytoplasm bilayer membranes, are responsible for several cell functions [1][2][3]. These

• chiral biomolecules have an asymmetric sn-glycerol backbone. Although sn-glycerol is symmetric, an sn-3 phosphate group makes it chiral with an (R)-configuration at the sn-2 position [4]. Such molecular chirality is crucial to not only their biological activities but also for their metaphysical

From chemical metabolism to life: the origin of the genetic coding process

• Antoine Danchin

Beilstein J. Org. Chem. 2017, 13, 1119–1135, doi:10.3762/bjoc.13.111

• atomic composition of matter: N for nitrogen, Fe, for iron, C for carbon). Thus a chemical molecule is information-rich. sn-Glycerol-3-phosphate can be described, including an outline of its three-dimensional configuration, by a limited alphabet of symbols (e.g., the Simplified Molecular Input Line Entry

• Specification (SMILES) code table [8]), C([C@H](COP(=O)(O)O)O)O, while its mirror symmetry sn-glycerol-1-phosphate is summarised as C([C@@H](COP(=O)(O)O)O)O. That this coding is sufficient (if associated to a concrete machine) is visible in Figure 1, where I used these codes with an algorithm to generate the

An easy α-glycosylation methodology for the synthesis and stereochemistry of mycoplasma α-glycolipid antigens

• Yoshihiro Nishida,
• Yuko Shingu,
• Yuan Mengfei,
• Kazuo Fukuda,
• Hirofumi Dohi,
• Sachie Matsuda and
• Kazuhiro Matsuda

Beilstein J. Org. Chem. 2012, 8, 629–639, doi:10.3762/bjoc.8.70

• and characterized by other groups [11][12][13][14]. Absolute chemical structures of GGPL-I [15] and GGPL–III [16] have already been established by chemical syntheses of stereoisomers; these α-glycolipids have a common chemical backbone of 3-O-(α-D-glucopyranosyl)-sn-glycerol carrying phosphocholine at

• former synthetic works on 3-O-(α-D-glycopyranosyl)-sn-glycerol [27][28][29][30], chiral 1,2-O-isopropylidene-sn-glycerol has often been employed [29][30] as the acceptor substrate for different α-glycosylation reactions. In this case, however, attention should be paid to the acid-catalyzed migration of

• -isomers at the sugar H-1 signal as well as at the glycerol H-2 (Table 1). Natural GGPL-I and GGPL-III gave 1H NMR data very close to those of I-a, indicating that both have a common skeleton of 3-O-(α-D-glucopyranosyl)-sn-glycerol [15][16]. The glycerol moiety has two C–C single bonds. By free rotation