Nuclear Magnetic Resonance Spectroscopy of Acetylated Methyl Glycopyranosides of Aminohexoses. Characterization of an Aminohexose from Septacidin

Agahigian, H.; Vickers, G. D.; Saltza, M. H. von; Reid, Joyce A.; Cohen, Allen I.; Gauthier, H.

doi:10.1021/jo01015a031

“…The 1-alkoxy-2-acetoxy-3-acetylaminocyclohexanes (Ia and IIa) exhibit parallel but slightly smaller shifts in the resonances of the methine protons, and i t thus appears likely that the downfield shift in axial I-I3 lvhich accompanies the change in orientation of 1-1 1 from axial to equatorial in these derivatives may owe its origin principally to the interaction of the axial anisotropic inethoxyl or acetoxyl group a t Cl with axial I-13. A similar effect has recently been observed in acetylated methyl glycopyranosides of some aminohexoses (13). In the 2-bronio series (11, Im, and 111, IIm), equatorial H I is deshielded with respect t o axial 1-11 to a smaller extent (0.1-0.3 p.p.m.)…”

supporting

confidence: 75%

Cyclohexane Compounds: Vi. Nuclear Magnetic Resonance Spectra of Some Derivatives of the Stereoisomeric 3-Bromo-1,2-Cyclohexanediols and the 2-Bromo-1,3-Cyclohexanediols

Bannard¹

1966

Can. J. Chem.

3

0

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First-order analysis of the 60 Mc.p.s. proton magnetic resonance spectra of la-inethoxy-28-acetoxy-3m-bromocyclohexane, lor-methoxy-2m-acetoxy-3p-bromocyclohexane, la-inethoxy-2p-bromo-3m-acetoxycyclohexane, lm-methoxy-2m-bromo-3p-acetoxycyclohexa1~e, and the corresponding diol diacetates confirmed the stereochemical interrelationships of substituents which were assigned previously on chemical grounds, and demo~istrated that the compounds exist in chair conformations. The chemical shifts of the ~ilethoxy methyl and acetoxy methyl protons did not provide reliable criteria for the assignment of conformations to these substituents in this series. The coupling constants of the methine protons followed, in general, the pattern predicted by the ICarplus equation, and the smaller J 2 , 3 values observed in the cis,trans compou~lds relative to those in the trans,trans compoundsare interpreted mainly on the basis of conformational equilibration, upon which is superimposed a small dihedral angular distortion or a remote substituent orientatio~ial effect.Analysis of the multiplet patterns and chemical shifts of the methine protons in the nuclear magnetic resonance spectra of the stereoisomeric 1-methoxy-2-acetoxy-3-acetylaminocyclohexanes Ia and IIa, their ethoxy analogues (Ic and IIc), and certain of their derivatives (Ib-Ie and IIb-IIe) (1) permitted unambiguous assignment of both gross structure and conformation to these compounds. This work also indicated that the chemical --.

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“…A proton NMR study of the methyl glycoside tetraacetate derivative of this aminohexose was used to assign it as 4-amino-4-deoxy-L-gluco-pyranose, but unfortunately this was only undertaken at low resolution with a low field (60 MHz) NMR instrument. 6 On the basis of this work, the absolute configuration of spicamycin was inferred to be 6-(4-amino-4-deoxy-L-glycero-b-L-mannoheptopyranosylamino)-9H-purine. 7 More recently, anicemycin, an analog of spicamycin (Figure 1), has been isolated from an unrelated Streptomyces strain.…”

Section: Introductionmentioning

confidence: 90%

“…With these questions in mind, we first sought to confirm the reported stereochemistry for the carbohydrate motifs. The absolute configuration of septacidin has been tentatively assigned by Agahigian et al 6 Septacidin was acid hydrolyzed to the aminoheptose, which was subsequently converted to an aminohexose by cleavage of the C6-C7 bond by periodate oxidation. A proton NMR study of the methyl glycoside tetraacetate derivative of this aminohexose was used to assign it as 4-amino-4-deoxy-L-gluco-pyranose, but unfortunately this was only undertaken at low resolution with a low field (60 MHz) NMR instrument.…”

Section: Introductionmentioning

confidence: 99%

“…Second, the 4-deoxy-4-amino-L-heptosyl sugar motifs are reported to be gluco-heptose for septacidin, but manno-heptose for spicamycin. 1,2,[6][7][8] This crucial difference in the stereochemistry at the 2 0 -position has marked implications on the potential biosynthetic pathways for septacidins and spicamycins. Either the presence of a unique 2-epimerase functionality is implied or the two different aminoheptoses may be biosynthesized by entirely diverse pathways.…”

Section: Introductionmentioning

confidence: 99%

“…Methyl (phenyl 5-acetamido-4-O-benzoyl-3,5-dideoxy-8,9-Oisopropylidene-2-thio-D-glycero-alpha-D-galacto-2-nonulopyranosid)onate(6). To a solution of compound 5 1 (4.0 g, 8.8 mmol) in dichloromethane (80 ml) and pyridine (20 ml), benzoyl chloride (2.6 ml, 22.0 mmol) was added at 0 1C.…”

mentioning

confidence: 99%

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Biosynthesis of 4-aminoheptose 2-epimers, core structural components of the septacidins and spicamycins

Price

¹

,

Furukawa

²

,

Cheng

³

et al. 2014

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Septacidins and spicamycins are acylated 4-aminoheptosyl-β-N-glycosides produced by Streptomyces fimbriatus and S. alanosinicus, respectively. Their structures are highly conserved, but differ in the stereochemistry of the 4-aminoheptosyl residues. The origin of this stereochemistry is unknown, but is presumably because of the difference in their biosynthetic pathways. We have synthesized the septacidin 4-aminoheptose to verify the difference between septacidin and spicamycin. Isotopic enrichment studies were undertaken using S. fimbriatus, and show that the septacidin heptose is derived from the pentose phosphate pathway. This indicates conserved pathways leading to the biosynthesis of 4-amino-4-deoxy-L-gluco-heptose or 4-amino-4-deoxy-L-manno-heptose.

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Nucleosides and Nucleotides

Suhadolnik¹,

Reichenbach²

2000

Kirk-Othmer Encyclopedia of Chemical Technology

1

0

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The naturally occurring nucleoside and nucleotide antibiotics exist as either the C ‐ or N ‐glycosides. They include ezomycin A 1 (C 26 H 38 N 8 O 15 S), ezomycin B 1 (C 26 H 39 N 7 O 17 S), ezomycin C 1 (C 26 H 37 N 7 O 16 S), ezomycin A 2 (C 19 H 26 N 6 O 12 ), ezomycin B 2 (C 19 H 25 N 5 O 13 ), ezomycin C 2 (C 19 H 25 N 5 O 13 ), showdomycin (C 9 H 11 NO 6 ), isoshowdomycin (C 9 H 11 NO 6 ), maleimycin (C 7 H 7 NO 3 ), oxazinomycin (C 9 H 11 NO 7 ), pyrazomycin (pyrazofurin) (C 9 H 13 N 3 O 6 ), formycin (C 10 H 13 N 5 O 4 ), formycin B (C 10 H 12 N 4 O 5 ), oxoformycin B (C 10 H 12 N 4 O 6 ). These antibiotics contain a variety of purine and pyrimidine rings. The naturally occurring nucleoside/nucleotide antibiotics, which have been isolated from bacteria, fungi, blue‐green algae, and marine sponges, have proven to be useful biochemical probes in eucaryotic, procaryotic, viral, fungal, and plant systems. The purine nucleosides inhibit protein synthesis, RNA and DNA synthesis, and methyltransferases; they have antimycoplasmal, antiviral, hypotensive, antifungal, antimycobacterial, and antitumor activities and induce sporulation. The pyrimidine nucleosides inhibit protein synthesis, virus replication, RNA and DNA synthesis, and cAMP phosphodiesterase. The imidazole nucleosides inhibit nucleic acid synthesis. The diazepin nucleosides inhibit adenosine deaminase (ADA). The indole nucleosides inhibit bacteria, yeast, fungi, and viruses. The N ‐nucleotide antibiotics include agrocin 84 (C 21 H 34 N 6 O 16 P 2 ), thuringiensin (C 22 H 30 N 5 O 19 P), phosmidosine (C 16 H 24 N 7 O 8 P), fosfadecin (C 13 H 19 N 5 O 10 P 2 ), and fosfocytocin (C 12 H 20 N 4 O 13 P 2 ). Thuringiensin, produced by B. thuringiensis , is a β‐exotoxin that exerts its toxic action on insects and mammals through the inhibition of RNA polymerases. Phosmidosine inhibits pore formation of Botrytis cinerea and Aspergillus niger . Fosfadecin and fosfocytocin inhibit gram‐positive and gram‐negative bacteria.

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Nuclear Magnetic Resonance Spectroscopy of Acetylated Methyl Glycopyranosides of Aminohexoses. Characterization of an Aminohexose from Septacidin

Cited by 32 publications

References 1 publication

Cyclohexane Compounds: Vi. Nuclear Magnetic Resonance Spectra of Some Derivatives of the Stereoisomeric 3-Bromo-1,2-Cyclohexanediols and the 2-Bromo-1,3-Cyclohexanediols

Cyclohexane Compounds: Vi. Nuclear Magnetic Resonance Spectra of Some Derivatives of the Stereoisomeric 3-Bromo-1,2-Cyclohexanediols and the 2-Bromo-1,3-Cyclohexanediols

Biosynthesis of 4-aminoheptose 2-epimers, core structural components of the septacidins and spicamycins

Nucleosides and Nucleotides

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