Polyhydroxylated Cyclopentane β-Amino Acids Derived from d-Mannose and d-Galactose: Synthesis and Protocol for Incorporation into Peptides

A stereoselective synthesis of polyhydroxylated cyclopentane β-amino acids from hexoses is reported. The reaction sequence comprises, as key steps, ring-closing metathesis of a polysubstituted diene intermediate followed by the stereoselective aza-Michael functionalization of the resulting cyclopent-1-ene-1-carboxylic acid ester. Examples of synthesis of polysubstituted 2-aminocyclopentanecarboxylic acid derivatives starting from protected d-mannose and d-galactose are presented. A general protocol for the incorporation of these highly functionalized alicyclic β-amino acids into peptides is also reported.

Characterization of the low energy conformations and differential reactivities of D-glucose and Dmannose based oxepines

Carbohydrate-based oxepines are valuable intermediates for the synthesis of septanose carbohydrates. Here we report the characterization of the preferred conformations of D-glucose and D-mannose based oxepines 1 and 2 using computational chemistry and NMR spectroscopy. Monte Carlo conformational searches on 1 and 2 were performed, followed by DFT optimization and single-point energy calculations on the low energy conformations of each oxepine. Coupling constants were computed for all unique conformations at a B3LYP/6-31G(d,p)u+1s level of theory and weighted based on a Boltzmann distribution. These values were then compared to the experimental values collected using 3JH,H values collected from 1H NMR spectra. Information from the MC/DFT approach was then used in a least squares method that correlated DFT calculated and observed 3JH, H coupling constants.
The conformations of 1 and 2 are largely governed by a combination of the rigidifying enol ether element in combination with the reduction of unfavorable interactions. The vinylogous anomeric effect (VAE) emerged as a consequence, rather than a driver of conformations. Oxepine 1 showed greater reactivity in Ferrier rearrangement reactions relative to oxepine 2, in line with its greater %VAE.

ral Dmannose treatment suppresses experimental autoimmune encephalomyelitis via induction of regulatory T cells

D-mannose (D-m) is a glucose epimer found in natural products, especially fruits. In mouse models of diabetes and airway inflammation, D-m supplementation via drinking water attenuated pathology by modifying cellular energy metabolism, leading to the activation of latent transforming growth factor beta (TGF-β), which in turn induced T regulatory cells (Tregs). Given that Tregs are important in controlling neuroinflammation in experimental autoimmune encephalomyelitis (EAE) and likely in multiple sclerosis (MS), we hypothesized that D-m could also suppress EAE.

D-(+)-Mannose

from NACALAI TESQUE
11663-32 | 25G: 45.50 EUR

D-(+)-Mannose

from NACALAI TESQUE
21306-02 | 25G: 26.25 EUR

D-(+)-Mannose

from NACALAI TESQUE
21306-15 | 500G: 241.50 EUR

D-(+)-Mannose

from Abbexa
20-abx183971 | [ 100 g: Ask for price ] [ 25 g: Ask for price ] [ 500 g: Ask for price ]

D-(+) MANNOSE

from PhytoTechnology Laboratories
M486 | 10KG: 23.79 EUR

D-(+)-Mannose

from Pfaltz & Bauer
M02290 | 25G: 138.73 EUR

D-(+)-Mannose

from Glentham Life Sciences
GC7397-100 | 100: 63.30 EUR

D-(+)-Mannose

from Glentham Life Sciences
GC7397-100G | 100 g: 112.80 EUR

D-(+)-Mannose

from Glentham Life Sciences
GC7397-25 | 25: 23.80 EUR

D-(+)-Mannose

from Glentham Life Sciences
GC7397-250 | 250: 126.50 EUR

D-(+)-Mannose

from Glentham Life Sciences
GC7397-250G | 250 g: 189.60 EUR

D-(+)-Mannose

from Glentham Life Sciences
GC7397-25G | 25 g: 64.80 EUR

D-(+)-Mannose

from Glentham Life Sciences
GC7397-500 | 500: 229.30 EUR

D-(+)-Mannose

from Glentham Life Sciences
GC7397-500G | 500 g: 313.20 EUR

D-(+)-Mannose

from EWC Diagnostics
PCT0605-100G | 1 unit: 57.57 EUR

D-(+)-Mannose

from EWC Diagnostics
PCT0605-25G | 1 unit: 16.43 EUR

D-(+)-Mannose

from EWC Diagnostics
PCT0605-500G | 1 unit: 258.92 EUR

D-(+)-Mannose

from EWC Diagnostics
RM104-100G | 1 unit: 36.02 EUR

D-(+)-Mannose

from EWC Diagnostics
RM104-25G | 1 unit: 10.33 EUR

D-(+)-Mannose

from EWC Diagnostics
RM104-500G | 1 unit: 161.92 EUR

D-(+)-Mannose, 99%, from wood

from Glentham Life Sciences
GC8181-500 | 500: 332.20 EUR

D-(+)-Mannose, 99%, from wood

from Glentham Life Sciences
GC8181-500G | 500 g: 438.00 EUR

GDP-​α-D-​mannose disodium

from TargetMol Chemicals
T11382-10mg | 10mg: Ask for price

GDP-​α-D-​mannose disodium

from TargetMol Chemicals
T11382-1g | 1g: Ask for price

GDP-​α-D-​mannose disodium

from TargetMol Chemicals
T11382-1mg | 1mg: Ask for price
We found that D-m delayed disease onset and reduced disease severity in two models of EAE. Importantly, D-m treatment prevented relapses in a relapsing-remitting model of EAE, which mimics the most common clinical manifestation of MS. EAE suppression was accompanied by increased frequency of CD4+FoxP3+ Tregs in the central nervous system, suggesting that EAE suppression resulted from Treg cell induction by D-m. These findings suggest that D-m has the potential to be a safe and low-cost complementary therapy for MS.