Transparent Superhydrophobic Coatings of Silica Nanoparticles Using Functionalized Polyurethanes.

Superhydrophobic coatings are essential to prepare water-repellent surfaces, self-cleaning materials, etc. Silica nano-materials are often immobilized to different surfaces for imparting super-hydrophobicity. Direct coating of silica-nanoparticles is often challenging since it can easily be peeled off under different environments. Herein, we reported the use of properly functionalized polyurethanes to facilitate the strong binding of silica-nanoparticles to surfaces. The alkyne terminal polyurethane was synthesized by step-growth polymerization while click-reactions facilitated to post-functionalization using phenyl moiety and were characterized by 1 H, 13 C nuclear magnetic resonance (NMR) spectroscopies, and 1 H spin-lattice relaxation times (T1 s). Upon functionalization, the glass transition temperature (Tg) increased due to enhanced interchain interactions. Moreover, additives like di(propyleneglycol)dibenzoate showed a substantial plasticizing effect to compensate for the increase in Tg, an important parameter for low-temperature applications. NMR signatures the spatial interactions between various protons of grafted silica-nanoparticles and phenyl triazole functionalized polyurethanes, thus indicating the usefulness of polyurethanes to bind silica-nanoparticles. After coating functionalized silica-nanoparticles to leather using functionalized polyurethanes, a contact angle value of more than 157° was observed with retention of grain patterns of leather due to transparency. We anticipate the results to help design varieties of materials with superhydrophobicity where the structural integrity of the surfaces is retained.

Interaction between sodium dodecylsulfate (SDS) and pluronic L61 in aqueous medium: assessment of the nature and morphology of the formed mixed aggregates by NMR, EPR, SANS and FF-TEM measurements.

The interaction of copolymer L61 i.e., (EO)2(PO)32(EO)2 (where EO and PO are ethylene and propylene oxides, respectively) with surfactant SDS (sodium dodecylsulfate) in relation to their self-aggregation, dynamics and microstructures has been physicochemically studied in detail employing the Nuclear Magnetic Resonance (NMR), Electron Paramagnetic Resonance (EPR), Small-Angle Neutron Scattering (SANS), and Freeze-Fracture Transmission Electron Microscopy (FF-TEM) methods. The NMR self-diffusion study indicated a synergistic interaction between SDS and L61 forming L61-SDS mixed complex aggregates, and deuterium (2H) NMR pointed out the nonspherical nature of these aggregates with increasing [L61]. EPR spectral analysis of the motional parameters of 5-doxyl steraric acid (5-DSA) as a spin probe provided information on the microviscosity of the local environment of the L61-SDS complex aggregates. SANS probed the geometrical aspects of the SDS-L61 assemblies as a function of both [L61] and [SDS]. Progressive evolution of the mixed-aggregate geometries from globular to prolate ellipsoids with axial ratios ranging from 2 to 10 with increasing [L61] was found. Such morphological changes were further corroborated with the results of 2H NMR and FF-TEM measurements. The strategy of the measurements, and data analysis for a concerted conclusion have been presented.

NMR investigations on binding and dynamics of imidazolium-based ionic liquids with HEWL.

Molecular level insights on protein-ionic liquid (P-IL) interactions are beneficial for assessing protein stability, binding and dynamics. In the present work, interactions of ILs, namely, 1-butyl 3-methylimidazolium methyl sulfate (IL1), 1-butyl 3-methylimidazolium octyl sulfate (IL2) and 1-butyl 3-methylimidazolium chloride (IL3) with hen egg white lysozyme (HEWL) protein were investigated using solution-state nuclear magnetic resonance (NMR) spectroscopy. To ascertain the binding and dynamics from the perspective of both protein and IL, various ligand based NMR approaches such as selective and non-selective nuclear spin-relaxation (R1SEL and R1NS), saturation transfer difference (STD), difference of inversion recovery rate with and without target irradiation (DIRECTION), 35Cl line-shape and spin-relaxation, and protein back bone amide chemical shift perturbations (CSPs) from 1H-15N HSQC were utilized. Among the ILs investigated, IL2 experiences significant interaction relative to those of IL1 and IL3, as revealed by the combined R1SEL and R1NS analysis, which is further supported by STD NMR. CSP analyses of 1H-15N HSQC spectra of aqueous P-IL mixtures enabled to identify the potential binding sites of ILs with HEWL. Whereas, 15N longitudinal (R1) and transverse (R2) spin-relaxation rates and 15N{1H} heteronuclear nuclear Overhauser effect (hetNOE) data subjected to the model free analysis for IL2 yielded the rotational correlation times and order parameters of various residues of HEWL. Furthermore, the results could discern the nature of interactions between studied ILs and HEWL in terms of specific and non-specific interactions.

Thermodynamically stable vesicle formation of biodegradable double mPEG-tailed amphiphiles with sulfonate head group.

The development of efficient, biodegradable and biocompatible surfactants has become a pressing need because of adverse effects of surface-active compounds on the aquatic environment and human health. Cleavable surfactants containing a labile functional group have the ability to eliminate some of these problems. Consequently, PEGylated amphiphiles have found widespread applications in pharmaceutics, household purposes, and drug delivery. Herein we report synthesis and characterization of two novel amphiphiles which to our knowledge are the first examples of double PEG-tailed amphiphiles with an anionic head group. Considering their chemical structure, they are expected to be biodegradable, biocompatible, milder and less irritant than conventional surfactants. The solution behavior of these newly developed amphiphiles was thoroughly investigated in aqueous buffer (pH 7.0) at 25 °C. The surface activity of the compounds in aqueous buffer was studied by surface tension measurements. The self-assembly properties were investigated by various techniques such as fluorescence and NMR spectroscopy, dynamic light scattering, transmission electron microscopy, atomic force microscopy, and isothermal titration calorimetry. Both molecules were found to be surface active in water and exhibit spontaneous vesicle formation in the absence of any additives at room temperature. As in the cases of conventional surfactants, the self-assembly is driven by the hydrophobic effect. The vesicles produced in aqueous media were shown to encapsulate hydrophobic dyes and exhibit structural transitions upon addition of salts. The sensitivity of the vesicles to change in environments qualifies them for potential use in drug delivery.

Correction: Thermodynamically stable vesicle formation of biodegradable double mPEG-tailed amphiphiles with sulfonate head group.

[This corrects the article DOI: 10.1039/D0RA05613H.].

Selective binding and dynamics of imidazole alkyl sulfate ionic liquids with human serum albumin and collagen - a detailed NMR investigation.

The interaction of ionic liquid (IL) with protein is now becoming important as it stabilizes the protein due to the selective cation-anion combination of the IL. The binding and dynamics of the green solvents such as imidazole alkyl sulfate based ILs, viz., 1-butyl-3-methylimidazolium alkyl [where alkyl = hydrogen, methyl, octyl and dodecyl] sulfate, with two distinct model proteins, namely human serum albumin (HSA) and collagen in aqueous solution, have been investigated with the aid of solution nuclear magnetic resonance (NMR). Interactions of ILs with HSA and collagen have been probed at the atomistic level through NMR determined parameters, such as 1H line-shapes, selective and non-selective spin-lattice relaxation times (T1SEL & T1NS) and spin-spin relaxation times (T2). Furthermore, saturation transfer difference (STD) NMR has been used to monitor the spatial proximities of ILs with HSA and collagen. The results indicate that despite the type of protein (HSA or collagen), STD NMR of protein-IL mixtures exhibits responses only from the anionic part of the selected ILs. Also, a combination of T1SEL and T1NS measurements indicates the genuine protein-IL interaction. Furthermore, it was observed that the global binding affinity between IL and proteins is enhanced with an increase in alkyl chain length of the anionic portion of the IL. The present study thus highlights the role of the anionic part of ILs in the interaction with the selected proteins. The outcome of the present study provides an opportunity to design new ILs with a judicious choice of anionic and cationic parts for targeted functionalities.

Vesicle to micelle transition in the ternary mixture of L121/SDS/D2O: NMR, EPR and SANS studies.

Subtle changes in the microstructure and dynamics of the triblock copolymer L121, (ethylene oxide)5 (propylene oxide)68 (ethylene oxide)5i.e., E5P68E5, and sodium dodecylsulfate (SDS) system in aqueous medium were investigated using high-resolution nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR) and small-angle neutron scattering (SANS) methods. NMR self-diffusion measurements helped us to understand the nature of binding of SDS with L121, and the formation of their mixed aggregates. These results showed that even at low [SDS] (∼2 mM), the addition of L121 stabilized the dynamics of SDS. Furthermore, the increase in [SDS] resulted in progressive changes in the diffusion behavior of both SDS and L121. 13C chemical shift analysis revealed that preferential binding of L121 occurred on the SDS micelle surface. Deuterium (2H) NMR spin-relaxation data evidenced that the formed mixed aggregates were non-spherical in terms of relaxation rate changes, and slowed the dynamics. The rotational correlation times of mixed aggregates were estimated from EPR analysis. A SANS study indicated the presence of uni- and multi-lamellar vesicles of L121 at low [SDS]. The vesicles transformed to mixed L121-SDS micelles in the presence of a higher [SDS]. This was supported by the measurements of 2H NMR spin-relaxation and EPR rotational correlation times.

Endoscopic "step-up approach" using a dedicated biflanged metal stent reduces the need for direct necrosectomy in walled-off necrosis (with videos).

BACKGROUND AND AIMS: EUS-guided drainage using plastic stents may be inadequate for treatment of walled-off necrosis (WON). Recent studies report variable outcomes even when using covered metal stents. The aim of this study was to evaluate the efficacy of a dedicated covered biflanged metal stent (BFMS) when adopting an endoscopic "step-up approach" for drainage of symptomatic WON. METHODS: We retrospectively evaluated consecutive patients with symptomatic WON who underwent EUS-guided drainage using BFMSs over a 3-year period. Reassessment was done between 48 and 72 hours for resolution. Endoscopic reinterventions were tailored in nonresponders in a stepwise manner. Step 1 encompassed declogging the blocked lumen of the BFMS. In step 2, a nasocystic tube was placed via BFMSs with intermittent irrigation. Step 3 involved direct endoscopic necrosectomy (DEN). BFMSs were removed between 4 and 8 weeks of follow-up. The main outcome measures were technical success, clinical success, adverse events, and need for DEN. RESULTS: Two hundred five WON patients underwent EUS-guided drainage using BFMSs. Technical success was achieved in 203 patients (99%). Periprocedure adverse events occurred in 8 patients (bleeding in 6, perforation in 2). Clinical success with BFMSs alone was seen in 153 patients (74.6%). Reintervention adopting the step-up approach was required in 49 patients (23.9%). Incremental success was achieved in 10 patients with step 1, 16 patients with step 2, and 19 patients with step 3. Overall clinical success was achieved in 198 patients (96.5%), with DEN required in 9.2%. Four patients failed treatment and required surgery (2) or percutaneous drainage (2). CONCLUSIONS: The endoscopic step-up approach using BFMSs was safe, effective, and yielded successful outcomes in most patients, reducing the need for DEN.

Physicochemical perspectives (aggregation, structure and dynamics) of interaction between pluronic (L31) and surfactant (SDS).

The influence of the water soluble non-ionic tri-block copolymer PEO-PPO-PEO [poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)] i.e., E2P16E2 (L31) on the microstructure and self-aggregation dynamics of the anionic surfactant sodium dodecylsulfate (SDS) in aqueous solution was investigated using cloud point (CP), isothermal titration calorimetry (ITC), high resolution nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR), and small-angle neutron scattering (SANS) measurements. CP provided the thermodynamic information on the Gibbs free energy, enthalpy, entropy and heat capacity changes pertaining to the phase separation of the system at elevated temperature. The ITC and NMR self-diffusion measurements helped to understand the nature of the binding isotherms of SDS in the presence of L31 in terms of the formation of mixed aggregates and free SDS micelles in solution. EPR analysis provided the micro-viscosity of the spin probe 5-DSA in terms of rotational correlation time. The SANS study indicated the presence of prolate ellipsoidal mixed aggregates, whose size increased with the increasing addition of L31. At a large [L31], SANS also revealed the progressive decreasing size of the ellipsoidal mixed aggregates of SDS-L31 into nearly globular forms with the increasing SDS addition. Wrapping of the spherical SDS micelles by L31 was also corroborated from (13)C NMR and SANS measurements.

Crystal structure of (Z)-2-(1-benzyl-2-oxoindolin-3-yl-idene)-N-phenyl-hydra-zine-1-carbo-thio-amide.

The title compound, C22H18N4OS, crystallized with four independent mol-ecules (A, B, C and D) in the asymmetric unit. All four mol-ecules have a Z conformation about the C=N bond with the benzyl ring being inclined to the indoline ring mean planes by 73.4 (2), 77.9 (2), 73.2 (2) and 77.2 (2)° in mol-ecules A, B, C and D, respectively. In mol-ecules A and B, the phenyl ring is inclined to the mean plane of the indoline ring mean plane by 12.0 (2) and 12.2 (2)°, respectively. However, in mol-ecules C and D, the same dihedral angles are larger, viz. 37.3 (2) and 36.4 (2)°, respectively. Consequently, the benzyl and phenyl rings are almost normal to one another in mol-ecules A and B [dihedral angles = 80.3 (3) and 87.1 (3)°, respectively], while in mol-ecules C and D, the same dihedral angles are only 48.8 (2) and 43.8 (3)°, respectively. There is an intra-molecular N-H⋯O hydrogen bond in each mol-ecule with an S(6) ring motif. There are also short intra-molecular N-H⋯N and C-H⋯S contacts in each mol-ecule. In the crystal, mol-ecules are linked via C-H⋯S hydrogen bonds and C-H⋯π inter-actions, forming a three-dimensional structure. The crystal was refined as a non-merohedral twin with a final BASF value of 0.110 (1).

Micellization and related behavior of sodium dodecylsulfate in mixed binary solvent media of tetrahydrofuran (Tf) and formamide (Fa) with water: a detailed physicochemical investigation.

The detailed aggregation behavior of sodiumdodecyl sulfate (SDS) in tetrahydrofuran (Tf)-water (W) and formamide (Fa)-water (W) media at varied volume percent compositions has been investigated. Surface tension (ST), conductance (Cond), viscosity (Visc), isothermal titration calorimetry (ITC), nuclear magnetic resonance (NMR) and small angle neutron scattering (SANS) were used in this study. The presence of nonaqueous solvents affected the critical micelle concentration (CMC) of SDS, the counter-ion binding of the micelle, the energetics of the air/water interfacial adsorption and micellization of the amphiphiles in the bulk, the ion-association (ion-pair, triple-ion, quadruple, etc. between Na(+) and DS(-) ions) as well as the weakly soluble (aggregation less) amphiphile solution. Tf has been observed to produce a "dead zone" or "non-micelle formation zone" in the mixed Tf-W domain of 10-40 vol%. Fa influenced the SDS aggregation up to 70 vol%, at higher proportions (below the Krafft temperature (K(T))), instead of the micelle, "randomly arranged globular assembly" (RAGA) was formed. The correlation of the standard free energy of micellization (ΔG(m)(0)) with different solvent parameters (1) dielectric constant (ε), (2) viscosity (η0), (3) Reichardt parameter (E(T)(30)), (4) Gordon parameter (G), and (5) Hansen-Hildebrand hydrogen bonding parameter (δ(h)) has been attempted. It has been found that δ(h) produced a master correlation between ΔG(m)(0) and δ(h) for different binary mixtures such as Tf-W, Fa-W, Ml-W and Dn-W.

(13)C NMR investigations and the molecular order of 4-(trans-4'-hexylcyclohexyl)-isothiocyanatobenzene (6CHBT).

The static 1D (13)C and 2D Proton Encoded Local Field (PELF) NMR experiments are carried out in the nematic phase of a less viscous liquid crystal 4-(trans-4'-hexylcyclohexyl)-isothiocyanatobenzene (6CHBT) with a view to find orientational order. The PELF spectra provide better resolution which facilitates the assignment of cyclohexyl and phenyl ring carbons relatively easy. For the cyclohexyl unit, four pairs of dipolar splitting are clearly noticed in contrast to earlier reports on structurally similar mesogens where only two pairs of doublets are seen. The linear relationship between anisotropic chemical shifts and orientational order is established and semi-empirical parameters are obtained to aid the study of the order behaviour of 6CHBT over the entire nematic range. The data further fitted to the Haller equation and a reasonably good agreement is observed. The temperature dependence trends of orientational order parameters extracted for various carbons using (13)C-(1)H dipolar couplings with those of (13)C chemical shifts are compared. A gradual decrease in the order parameter is noticed for different molecular segments while traversing from the core to the aliphatic chain via the cyclohexyl ring. The notable decreasing trends of order parameters along the chain are observed similar to those of the corresponding phenyl cyclohexanes reported earlier.

Influence of water-insoluble nonionic copolymer E(6)P(39)E(6) on the microstructure and self-aggregation dynamics of aqueous SDS solution-NMR and SANS investigations.

The influence of water-insoluble nonionic triblock copolymer PEO-PPO-PEO [poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)] i.e., E6P39E6 with molecular weight 2800, on the microstructure and self-aggregation dynamics of anionic surfactant sodium dodecylsulfate (SDS) in aqueous solution (D2O) were investigated using high resolution nuclear magnetic resonance (NMR) and small-angle neutron scattering (SANS) measurements. Variable concentration and temperature proton ((1)H), carbon ((13)C) NMR chemical shifts, (1)H self-diffusion coefficients, (1)H spin-lattice and spin-spin relaxation rates data indicate that the higher hydrophobic nature of copolymer significantly influenced aggregation characteristics of SDS. The salient features of the NMR investigations include (i) the onset of mixed micelles at lower SDS concentrations (<3 mM) relative to the copolymer-free case and their evolution into SDS free micelles at higher SDS concentrations (~30 mM), (ii) disintegration of copolymer-SDS mixed aggregate at moderate SDS concentrations (~10 mM) and still binding of a copolymer with SDS and (iii) preferential localization of the copolymer occurred at the SDS micelle surface. SANS investigations indicate prolate ellipsoidal shaped mixed aggregates with an increase in SDS aggregation number, while a contrasting behavior in the copolymer aggregation is observed. The aggregation features of SDS and the copolymer, the sizes of mixed aggregates and the degree of counterion dissociation (α) extracted from SANS data analysis corroborate reasonably well with those of (1)H NMR self-diffusion and sodium ((23)Na) spin-lattice relaxation data.

The metabolic advantage of choline lactate in growth media: an experimental analysis with Staphylococcus lentus.

The metabolic effectiveness of choline lactate in the growth media was investigated relative to conventional carbon source for growing Staphylococcus lentus, a bacterial strain commonly used in bioremediation of industrial effluents and xenobiotic detoxification. Bacterial growth thermodynamics was determined by biocalorimetry. (13)C NMR and FTIR spectroscopic analyses traced the consumption of choline lactate at specific time intervals of bacterial growth. Under aerobic conditions, it is apparent that S. lentus initially metabolized lactate for its energy needs, while the choline cation of the ionic salt seemed to provide its C and N for biosynthetic intermediates for cell structure/function, in the growing bacterial colony. Urea accumulation after 40 h of bacterial growth was recorded. Possible metabolic trajectory of choline lactate consumed during S. lentus growth is suggested here. The theoretical estimation of heats of reaction for the proposed metabolic pathway (455 kJ/mol) was comparable with the experimentally obtained reaction enthalpy (435 kJ/mol), which further validated the proposed metabolic pathway. The biomass and energy profile of bacteria growth in choline media was found to be more favorable than in glucose media. The ionic liquid, choline lactate, offers a metabolically and energetically efficient carbon (and nitrogen) source for growing S. lentus.

Amphiphile behavior in mixed solvent media I: self-aggregation and ion association of sodium dodecylsulfate in 1,4-dioxane-water and methanol-water media.

Mixed aquo-organic solvents are used in chemical, industrial, and pharmaceutical processes along with amphiphilic materials. Their fundamental studies with reference to bulk and interfacial phenomena are thus considered to be important, but such detailed studies are limited. In this work, the interfacial adsorption of sodium dodecylsulfate (SDS, C12H25SO4(-)Na(+)) in dioxane-water (Dn-W) and methanol-water (Ml-W) media in extensive mixing ratios along with its bulk behavior have been investigated. The solvent-composition-dependent properties have been identified, and their quantifications have been attempted. The SDS micellization has been assessed in terms of different solvent parameters, and the possible formation of an ion pair and triple ion of the colloidal electrolyte, C12H25SO4(-)Na(+) in the Dn-W medium has been correlated and quantified. In the Ml-W medium at a high volume percent of Ml, the SDS amphiphile formed special associated species instead of ion association. The formation of self-assembly and the energetics of SDS in the mixed solvent media have been determined and assessed using conductometry, calorimetry, tensiometry, viscometry, NMR, and DLS methods. The detailed study undertaken herein with respect to the behavior of SDS in the mixed aquo-organic solvent media (Dn-W and Ml-W) is a new kind of endeavor.

Gitelman's syndrome with panhypopituitarism: Reno-endocrine interplay.

Gitelman's syndrome is an inherited tubulopathy affecting thiazide-sensitive sodium chloride cotransporter, which manifests with hypokalemic alkalosis, hypomagnesemia, and hypocalciuria. Recently few cases have been described having an association of Gitelman's syndrome with pituitary abnormalities on imaging, though with normal hormonal status. We describe the first case of an adult patient having Gitelman's syndrome and hypopituitarism with abnormal pituitary imaging. She presented to us with hypotension, hypokalemia, hypomagnesemia with alkalosis, hypothyroidism, hypocortisolism, and hypogonadism. She was treated with replacement of electrolytes and hormones, to which she showed an excellent response.

Regioselective synthesis and structural elucidation of 1,4-disubstituted 1,2,3-triazole derivatives using 1D and 2D NMR spectral techniques.

Regioselective synthesis of 2-[1-(2-oxo-2-phenylethyl)-1H-[1,2,3]triazol-4-ylmethoxy]-benzaldehyde derivatives was achieved by [3 + 2] cycloaddition reaction of 2-(prop)-2-ynyloxy-benzaldehyde derivatives with phenacyl azide. The regiochemistry and the spectral assignments of the synthesized triazole derivatives were studied using both 1D and 2D NMR spectral techniques in solution.

NMR investigations of self-aggregation characteristics of SDS in a model assembled tri-block copolymer solution.

The present work was undertaken with a view to understand the influence of a model non-ionic tri-block copolymer PEO-PPO-PEO (poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)) with molecular weight 5800 i.e., P123 [(EO)(20)-(PO)(70)-(EO)(20)] on the self-aggregation characteristics of the anionic surfactant sodium dodecylsulfate (SDS) in aqueous solution (D(2)O) using NMR chemical shift, self-diffusion and nuclear spin-relaxation as suitable experimental probes. In addition, polymer diffusion has been monitored as a function of SDS concentration. The concentration-dependent chemical shift, diffusion data and relaxation data indicated the significant interaction of polymeric micelles with SDS monomers and micelles at lower and intermediate concentrations of SDS, whereas the weak interaction of the polymer with SDS micelles at higher concentrations of SDS. It has been observed that SDS starts aggregating on the polymer at a lower concentration i.e., critical aggregation concentration (cac=1.94 mM) compared to polymer-free situation, and the onset of secondary micelle concentration (C(2)=27.16 mM) points out the saturation of the 0.2 wt% polymer or free SDS monomers/micelles at higher concentrations of SDS. It has also been observed that the parameter cac is almost independent in the polymer concentrations of study. The TMS (tetramethylsilane) has been used as a solubilizate to measure the bound diffusion coefficient of SDS-polymer mixed system. The self-diffusion data were analyzed using two-site exchange model and the obtained information on aggregation dynamics was commensurate with that inferred from chemical shift and relaxation data. The information on slow motions of polymer-SDS system was also extracted using spin-spin and spin-lattice relaxation rate measurements. The relaxation data points out the disintegration of polymer network at higher concentrations of SDS. The present NMR investigations have been well corroborated by surface tension and conductivity measurements.

Synthesis and NMR spectral assignments of indol-3-yl pyridines through one-pot multi-component reaction.

Asimple protocol for the efficient preparation of 6-(ferrocene-1-yl)-2-(indol-3-yl)pyridine and 2-(1H-indol-3-yl)-6-(2-thienyl)pyridine derivatives has been achieved through multi-component reaction, and these compounds were thoroughly characterised by 2D NMR spectral techniques.

Synthesis of densely functionalised C-glycosides by a tandem oxy Michael addition-Wittig olefination pathway.

Wittig olefination of 5,6-dideoxy-5,6-anhydro-6-nitro-D-glucofuranose (5) triggered a concomitant cyclisation via oxy Michael addition of the C2-hydroxyl group resulting in the formation of C-vinyl glycosides with Z-olefinic geometry.