2-Oxo-3R,4S,5S,6S-tetraethoxyazepane was conveniently synthesized from D-glucono-1, 5-1actone with a yield of 10% overall. The key step of synthetic route-reductive 1,6-cyclization was completed efficiently by using P...2-Oxo-3R,4S,5S,6S-tetraethoxyazepane was conveniently synthesized from D-glucono-1, 5-1actone with a yield of 10% overall. The key step of synthetic route-reductive 1,6-cyclization was completed efficiently by using Ph3P to give the expected lactam.展开更多
The alkali-hydrolysis of D-glucono-delta-lactone (GDL) was investigated by chiral Raman and circular dichroism (CD) spectroscopies in combination with density functional theory calculation. Based on the characteristic...The alkali-hydrolysis of D-glucono-delta-lactone (GDL) was investigated by chiral Raman and circular dichroism (CD) spectroscopies in combination with density functional theory calculation. Based on the characteristic CD bands of GDL and its hydrolysis product, the dynamics of hydrolysis was studied using stopped-flow CD method. Using chiral Raman spectroscopy (CRS), the stereochemical change of GDL owing to the hydrolysis reaction was discussed on the vibrational scale. The CRS results show that the ring-opening due to hydrolysis has a great influence on the chiral structure around the car-bonyl group, which was evidenced by the disappearance of the CRS band at 1735 cm-1 (C== O stretching vibrational mode). In addition, the change of positions and intensity of CRS bands was also observed, which was ascribed to the perturbation around the C2, C3, C4 and C5 carbons due to ring-opening. It is worthy to note that the stereochemistry of C2, C3, C4 and C5 had no fundamental change during the hydrolysis reaction, which was reflected in the maintenance of the signs of the CRS bands. Our results demonstrate that in comparison with CD technique, CRS may provide more detailed structural information of chiral molecules and open up new vistas of research for chiral reactions.展开更多
The method of preparation of calcium gluconate with eggshell and glucono delta lactone was studied.The results showed that the yield of calcium gluconate can reach 71.42% under the optimum conditions.
基金the Graduate Education Innovation Foundation of Nanjing University of Science & Technology (No.200705).
文摘2-Oxo-3R,4S,5S,6S-tetraethoxyazepane was conveniently synthesized from D-glucono-1, 5-1actone with a yield of 10% overall. The key step of synthetic route-reductive 1,6-cyclization was completed efficiently by using Ph3P to give the expected lactam.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 20621063, 20773123, and 20673110)Programme for Strategic Scientific Alli-ances between China and the Netherlands (Grant No. 2008DFB50130)
文摘The alkali-hydrolysis of D-glucono-delta-lactone (GDL) was investigated by chiral Raman and circular dichroism (CD) spectroscopies in combination with density functional theory calculation. Based on the characteristic CD bands of GDL and its hydrolysis product, the dynamics of hydrolysis was studied using stopped-flow CD method. Using chiral Raman spectroscopy (CRS), the stereochemical change of GDL owing to the hydrolysis reaction was discussed on the vibrational scale. The CRS results show that the ring-opening due to hydrolysis has a great influence on the chiral structure around the car-bonyl group, which was evidenced by the disappearance of the CRS band at 1735 cm-1 (C== O stretching vibrational mode). In addition, the change of positions and intensity of CRS bands was also observed, which was ascribed to the perturbation around the C2, C3, C4 and C5 carbons due to ring-opening. It is worthy to note that the stereochemistry of C2, C3, C4 and C5 had no fundamental change during the hydrolysis reaction, which was reflected in the maintenance of the signs of the CRS bands. Our results demonstrate that in comparison with CD technique, CRS may provide more detailed structural information of chiral molecules and open up new vistas of research for chiral reactions.
文摘The method of preparation of calcium gluconate with eggshell and glucono delta lactone was studied.The results showed that the yield of calcium gluconate can reach 71.42% under the optimum conditions.
