Saccharose structure

FIGURE 1.1 Structures of organic compounds referred to in the text (a) sucrose (also known as saccharose), (b) dimethyl sulfoxide (DMSO), (c) dimethylformamide (DMF), (d) sorbitol, (e) mannitol, (f) nitrilotriacetic acid (NTA), (g) citric acid, (h) N,N,N, N -fran,s-1,2-diaminocyclohexane-tetraacetic acid (CyTA), (i) saccharic acid, (j) glutamic acid. 

The selective functionalization of saccharose and sorbitol with fatty acids for the construction of a perfect amphiphilic structure cannot be realized in simple technical processes because of the polyfunctionality of the molecule. This is why the products offered on the market contain different amounts of mono-, di- and... 

We implement a modified version of the reconstruction method developed in a previous work to model two porous carbons produced by the pyrolysis of saccharose and subsequent heat treatment at two different temperatures. We use the Monte Carlo g(r) method to obtain the pair correlation functions of the two materials. We then use the resulting pair correlation functions as target functions in our reconstruction method. Our models present structural features that are missing in the slit-pore model. Structural analyses of our resulting configurations are useful to characterize the materials that we model. 

We prepared two carbons by pyrolysis of saccharose followed by heat treatment at two different temperatures 400 C (CS400) and 1000"C (CSIOOO). We performed X-ray diffraction and SAXS on each of these porous materials and obtained the structure factors, S q), following the procedure described by Franklin [14]. The resulting S(q) s are shown in Figure 1 (bold line). We performed Hg porosimetry to obtain the density of both carbons, accounting for the volume occupied by C atoms, closed pores and smaller open pores. We also measured the H/C and the O/C ratios by combustion experiments. The results are summarized in Table 1. 

Figure 1. Structure factors of saccharose-based carbons obtained from diffraction experiments (bold line) and MCGR fit (thin line), a) CS400, b) CSIOOO...

Structural studies of saccharose- and anthracene-based carbons by high energy X-ray scattering. 

Fig. 1. The structure factors S(K) for the saccharose- and the anthracene-based carbons annealed at 1000°C, 1900 C and 2300"C.

It will be necessary, now, to consider the stereo-isomerism of those mono-saccharoses which contain more than three carbon atoms. The isomerism of the aldoses and ketoses is structural, depending upon the different groups present in the molecule. These two isomeric forms of the mono-saccharoses are found in the case of each member above the bi-ose group, as this can exist only in the condition of an aldehyde compound and not as a ketone. If we examine the structural formula of any mono-saccharose containing more than three carbons we shall find that they each contain at least one asymmetric carbon atom. In most cases two or more asymmetric carbons are present, as shown in the following formulas in which the asymmetric carbon atoms are marked. 

Neubauer H, Meiler J, Peti W, Griesinger C. NMR structure determination of saccharose and raffinose by means of homo- and heteronuclear dipolar couplings. Helv Chim Acta 2001 84(1) 243-258. 

The structure of carbohydrates can also play an important role for flavour sorption. Studies of Niediek and Babemics [58] deal with the flavour sorption properties of amorphous saccharose and lactose. So far, they were able to confirm that the sorption capability in the amorphous state is considerably higher than in the crystalline state. 

Rouzaud, J.N. and Oberlin, A. (1989). Structure, microtexture, and optical properties of anthracene and saccharose-based carbons. Carbon, 27, 517-29. 

Figure 5.2 Pair correlation functions of the saccharose-based carbons (a) CS400 and (b) CSIOOO target (sobd line) and converged CRMC structure (dashed line). (Adapted from Ref. [27].)...

Before 1960, one of main components of olive, the oleuropein, was studied in Roma. Panizzi s research group established the structure of this monoterpene glucoside, die leader of the group, that only several years later was identified as secoiridoids. Panizzi s group has isolated two other compounds the oleuropeic acid that is a monocyclic monoterpene, and its saccharose derivative. 

In the early researches on 0. europaea, [35], Panizzi demonstrated that oleuropeic acid 31, the 4-( 1. hydroxyisopropyl> 1 -cycloexene-1 -carboxylic acid, occurs in the root bark of (). europaea, mainly as a sucrose ester, i.e. the 6-O-oleuropeil saccharose 32 (see Figure 14). The structure of 31 was determined by comparison with an authentic sample [36-38]. The demonstration of the position of ester linkage in oleuropeil saccharose 32 was achieved with a combination of enzymatic and chemical reactions [39]. 

The chemistry of natural products encompasses their isolation, structure elucidation, partial and total synthesis, elucidation of their biogenesis, and the biomi-metic synthesis of N. p. Major breakthroughs in analysis were, e.g., the structural clarifications of morphine, lignin, insulin, estrones, and cholesterol as well as the elucidation of the biosyntheses of terpenoids, morphine, penicillin, chlorophyll, and vitamin B 2. Major advances in synthetic chemistry were, e.g., the total syntheses of camphor, hemin, quinine, saccharose, tropine, stryehnine, chlorophyll, vitamin B 2, erythromycin, taxol and palytoxin. Numerous N. p. of the so-ealled ehiral pool are used as starting materials for the synthesis of optically active compounds or serve (in the form of their derivatives) as catalysts for enantioselective syntheses. 

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