interpretation at the end of page
tablePeak List Date: 23.07.2000 Time: 19:18 File Name: c: \ mydocu ~ 1 \ carvone \ picccarv \ 001001.1R Peak Results saved in File: - Peak Picking Parameter: Peak constant PC: 1.00 Noise: 32624 Sens. Level: 130495 Peak Picking region: Start (ppm) Start (Hz) End (ppm) End (Hz) MI (%) MAXI (%) 3999.5 643.0 8.00 1.29 2.53 100.00 Peak Picking results: Nr. Data Point Frequency PPM Intensity% Int. 1 27,086,716 8.7 6.6736 3337.67 14 963 2 14 968 11.3 3336.44 6.6711 35.30668 million 6.6687 37,279,372 14 973 3 11.9 3335.21 6.6657 34,489,456 4 14 979 11.0 3333.73 6.6623 33,366,342 14 986 5 10.7 3332.01 6 14 992 11.3 3330.53 6.6593 35.16274 million 7 14 997 11.0 3329.30 6.6569 34.35534 million 3327.82 15 003 8 26,249,558 8.4 6.6539 4.7102 62,156,552 9 18 953 19.9
13C-NMR (COM, DEPT)
Carbon than the sum of protons, C10 H14 (134 formula weight), and 16 out of 150 molecular weight. δ199.4 carbonyl signal (C = O) is estimated to be, can be determined with the molecular formula C10H14O. Degree of unsaturation (C +1- H / 2) = 4 and is estimated to carbon double bond and two of four from 110.3 δ146.5, leaving one degree of unsaturation together with one carbonyl According to the ring can be estimated.
The one-dimensional 1H spectra in the side-swing write a letter to the peak of the NMR spectra, summarized in the table the correlation. Ground shaking in alphabetical HMQC spectra see the next section. If you do the same if drawn in order to analyze only the low-field COSY.
Here, they reveal the following partial structure.
- j (CH3) - c (CH) (estimated from the δ-allyl coupling we value and c J)
- i (CH3) - e '(CH2) (estimated from the δ-allyl coupling we value and c J). That i (CH3) - (C) = e '(CH2)
- Structure, including the first part, j (CH3) - (C) = c (CH) - h, h '(CH2) - g (CH) - f, f' (CH2)
Only from COSY and 1H-NMR, the structure of some compounds can be estimated. Identification is performed to obtain the data or preparation at the time of construction was estimated. Compounds are also present here can be estimated ccarvone would continue as a unknown compound below.
- A low magnetic field side of the carbon, b, c. ... and shake the alphabet.
- Alphabetical shake directly linked to the proton. If the methylene protons of the inequality is correlated with higher magnetic field back out of two protons and one carbon "'" give.
This spectrum becomes incomplete decoupling c-axis across the carbon peak is completely decoupled j is not.
Fill in the spectrum of the same alphabet shaken by HMQC.
Between protons and carbon through the binding of two or three there is a coupling of a few Hz (coupling distance, long-rangecoupling,, LRJCH ,2-3JCH). Similar peaks are not involved in measuring HMQC "turn phase" and "gradient pulse" so that off with a caution because it may appear Upon analysis of the spectrum . There may appear to be direct correlation between carbon and proton, which do not divide by 1JCH carbon decoupling (e, j, i). If you have a location just one proton, the observed correlation and unerring attention to this remote. Create a correlation table shown below, to be analyzed. Direct proton - carbon position in the Q, HMBC correlations will fill O. If you can not determine whether it has given not correlate with chemical shift is close to f and g of carbon length across the circle to fill in the table below it. Focus on the correlation structure connecting the estimated area so far. Carbon / proton = a / c, a / j, which leads to the planar structure by g / i. Also, b / i, a quaternary carbon by b d / j, which can be attributed the d.
Then fill all the HMBC correlations led to the structure, there is no place to check whether the correlation is not connected. Also, make a table similar to the above table, entering the number of protons and carbon within three bonds if it was this structure. To check for inconsistencies in comparison with the above table. Here is some correlation with the circle. HMBC measurements to set the delay time 1/2J. J values deviate significantly from having a carbon value - can hardly be the correlation between the protons. Coupling constant values refer to the remote data collection. Protons through the coupling of two or three - and even out the carbon is not always correlated. More than four out of the correlation, however, are accustomed to explain why such should be able to shape W.
NOESY, NOE difference spectra
A method to detect the spatial proximity between protons. Relative configuration, perform the attribution of methylene inequality. NOESY spectrum diagonal peak is negative (red), normally a positive NOE peak (black) was obtained at a peak negative exchange unwanted peak sometimes appear in the form of a COSY peak dispersion. Also used one-dimensional NOE difference spectra performed by irradiating a particular proton. Irradiation position is negative, becomes positive NOE, would like spectrum and cross section of the NOESY diagonal peak position and the irradiation position exactly.
When considering the stereochemistry molecular model formed a let.
E in the NOESY spectra, focusing on the methylene protons e ', e' is on the ring protons, e is this inequality can be attributed from the fact that the methylene gives NOE correlations of methyl protons of i. h, h ', f, the attribution of methylene inequality f' (or the same side or opposite protons g) the molecular model is used. axial substituents on carbon and g is less likely because, equatorial substituents, axial proton next g, and this time, close to the adjacent methylene protons g and those of cis protons and g, the trans What can be seen farther. is rotatable between an e gb free, while the e 'is on the ring proton h, h', g, f, and f ', and can approach the other methyl protons of i.
Since h was observed in NOE difference spectrum upon irradiation of g in NOE, and cis protons of g can be attributed with this.
f, for f 'is a clear NOE correlation has not been obtained, can be reserved for the J coupling between the proton. From molecular models, f, g and those of the cis methylene protons f ', g and small values of J closer to 90 ° dihedral angle g, and those of trans dihedral angles near 180 ° The higher the expected value of g and J since. The largest division of the division of the methylene protons splitting pattern of protons and these show that it is aware geminal coupling, shows that large values of g and J f '. As shown below, can be estimated from these relative stereochemistry. one proton geminal f is one reason that despite being split into pieces ddd one vicinal proton can be estimated from molecular models will be W-shaped coupling h and the proton.
In addition, the asymmetric carbon and carbon-g, this compound is present in two optical isomers, by NMR to determine the absolute configuration is not to be derivatized.
Chemical methods for sprout control
A large number of chemicals have been shown to have sprout-inhibiting effects such as ethylene, nonanol, chlorpropham, maleic hydrazide, carvone, abscisic acid, indol acetic acid, clove oil, mint oils, hydrogen peroxide, and 1, 4-dimethylnaphthalene (Buitelaar, 1987; Kleinkopf et al., 2003; Rastovski, 1987a; van Es and Hartmans, 1987d). However, the principal sprout inhibitors used worldwide are isopropyl N-phenylcarbamate (IPC, propham) and isopropyl N-(3-chlorophenyl) carbamate (CIPC, chloro-IPC, chloropropham). Both compounds stop cell division and the effect is irreversible and hence cannot be used in seed tubers. The effectiveness of CIPC depends on the storage conditions, application technology, and variety characteristics (Buitelaar, 1987; Kleinkopf et al., 2003). IPC and CIPC are available in powders and liquids. CIPC is generally vaporized into piles of stored potatoes or applied in a water-based application to tubers being packed for grocery stores. The advantage of using powders is that they can be applied in a single operation which does not require excessive effort. However, the use of powder form results in irritation of the skin in potatoes if the potatoes are insufficiently suberized, resulting in the loss of natural color of potatoes (Buitelaar, 1987). The disadvantages of powder use are dust nuisance, natural color loss, and skin irritation, which can be reduced by using liquid form as the application is done in three treatments. The disadvantage of liquid form is it should be applied at an early stage, the first dose must be applied two or three weeks after the harvest (Buitelaar, 1987). Studies involving two chipping cultivars, Snowden and Monona, with or without Chlorpropham (CIPC) application, and stored in darkness at 10/12°C, showed no effect of CIPC on chip color quality or tuber concentrations of protein, dry matter, sucrose, reducing sugars, or the assayed enzymes and metabolites of glycolysis. Respiration, as measured by CO2 production, was significantly suppressed in CIPC-treated tubers. Concentrations of ethanol and lactate, products of anaerobic respiration, were significantly higher in the CIPC-treated Snowden tubers, relative to the untreated tubers (Blenkinsop et al., 2002). Maleic hydrazide is often used as a preharvest foliar spray and is popular and effective (Buitelaar, 1987). Although it can control sprouting for 3–4 months, a subsequent treatment with CIPC is required during later storage. A recent Environmental Protection Agency mandate (1996) within the requirements of the Food Quality Protection Act (FQPA) resulted in a reduction in allowable CIPC residue on fresh potatoes in the USA from 50 ppm to 30 ppm. This mandate coincides with tolerance reductions or restrictions for use of CIPC in other parts of the world (Kleinkopf et al., 2003). Hence there is a need for alternative compounds for sprout suppression. Naturally occurring volatile compounds such as mono-, di-, and trimethylnapthalenes, benzothiophene (DMN), 2, 6-diisopropylnapthalene (DIPN), carvone and ethylene have been found effective at lower temperatures (7–10°C) and at higher concentrations as compared to CIPC (Kalt et al., 1999; Lewis et al., 1997). Strong sprout-suppressing effect of carvone was also observed at higher storage temperatures (24 ± 2°C; Mehta Ashiv 2002). A concentration of 300 μl/l completely inhibited sprouting for 110 days of storage with no rotting up to 80 days. Due to its high volatility, repeated applications are required which may cost up to 10 times the cost of CIPC treatment. The advantage of using carvone is that it does not affect the fry color, its effect is reversible so that it can be used for treating seeds, and it has been shown to have fungicidal activity against silver scurf, some Fusarium, and Rhizoctonia (Mehta Ashiv, 2002). In a study to compare the sprout inhibition effect of various suppressants and its effect on fry color and sugar content during 25 weeks of storage at 9°C, it was observed that maximum suppression of sprouting was observed with CIPC followed by carvone, ethylene, and dimethylnapthalene (Kalt et al., 1999). Another report (Vokou et al., 1993) where the sprout inhibition and antimicrobial effect of various aromatic plants were studied, showed that essential oils of Lavandula angustifolia (lavender), Mentha pulegium (mint), Mentha spicata (spearmint), Rosmarinus officinalis (rosemary), and Salvia fruticosa (sage) suppressed sprout growth and had antimicrobial activity against Erwinia carotovora strains and bacteria isolated from the surface of potato tubers. The sprout inhibition was reversible, thus it can be used for seed tuber storage (Vokou et al., 1993).
Ethylene is a very effective sprout inhibitor, however, its use may result in darkening of fry color (Daniels-Lake et al., 2007). Like carvone, its effect is reversible and can be used for seed storage. In a study carried out to minimize the effect of ethylene on fry color, it was observed that continuous ethylene treatments inhibited sprout growth as effectively as CIPC, except at 13°C storage. Interruptions of 18 h and 2 or more days reduced sprout inhibition. It was also observed that an early start of ethylene exposure before the end of suberization using either a concentration or time-increment gradient had the least effect on fry color while maintaining good sprout inhibition (Daniels-Lake et al., 2007). Other emerging potent natural sprout inhibitors are salicylaldehyde and menthol which can be used under higher-temperature storage conditions (Mehta and Ezekiel, 2006).