ABSTRACT
Besides the peripheral modification, the introduction of heteroatoms to modulate the property of longer acenes with improved chemical stability has been extensively studied for their potential applications in organic electronics. However, the utilization of 4-pyridone, a common unit in the air- and photo-stable acridone and quinacridone, to decorate higher acenes with increased stability has not been realized yet. Here we present the synthesis of a series of monopyridone-doped acenes up to heptacene via the palladium-catalyzed Buchwald-Hartwig amination of aniline and dibromo-ketone. The effect of pyridone on the property of doped acenes were investigated experimentally and computationally. With the π-extension of doped acenes, the pyridone ring shows the weakened conjugation and gradual loss of aromaticity. The doped acenes demonstrate enhanced stability in solution and maintain the electronic communication between the acene planes.
ABSTRACT
OBJECTIVE: To evaluate the short-term effect and safety of entecavir for the treatment of chronic hepatitis B (CHB) virus carriers. METHODS: Ninety-three cases of CHB virus infection (hepatitis B surface antigen (HBsAg)-positive, hepatitis B e antigen (HBeAg)-positive, hepatitis B core antibody (HBcAb)-positive, HBV DNA≥1x10(5) copies/mL) were divided into two groups: CHB virus carrier (47 cases) and CHB (46 cases). All of the 93 cases were given 0.5 mg entecavir orally once a day for 48 weeks. Virology, serology and biochemistry tests were perrmed at treatment weeks 0, 4, 12, 24 and 48. Side effects of entecavir and the incidence of liver cirrhosis and hepatocellular carcinoma were recorded. RESULTS: The CHB virus carrier and CHB group had complete virological response rates of 14.9% and 17.4% at week 4, 51.1% and 63.0% at week 12, 76.6% and 89.1% at week 24, and 97.9% and 100% at week 48, respectively; there was no significant difference between the two groups (P>0.05). The CHB virus carrier and CHB group had partial virological response rates of 42.6% and 47.8% at week 4, 57.44% and 65.2% at week 12, 85.0% and 89.1% at week 24, and 100% and 100% at week 48, respectively; there was no significant difference between the two groups (P>0.05). No cases in either group experienced virologic breakthrough during the treatment course. The CHB virus carrier and CHB group had serological response (HBeAg-negative) rates of 0 and 4.3% at week 4, 2.1% and 8.7% at week 12, 4.3% and 13.0% at week 24, and 8.5% and 21.7% at week 48, respectively; there was no significant difference between the two groups (P>0.05). The CHB virus carrier and CHB group had HBeAg seroconversion rates of 0 and 0 at week 4, 0 and 4.4% at week 12, 2.1% and 10.9% at week 24, and 6.4% and 17.4% at week 48, respectively; there was no significant difference between the two groups (P>0.05). No case in either group showed HBsAg-negativity and seroconversion during the treatment course. The CHB group had a biochemical response (alanine aminotransferase normalization) rate of 26.1% at week 4, 65.2% at week 12, 91.3% at week 24, and 97.8% at week 48.No case in either group showed biochemical breakthrough during the treatment course. There were no cases of liver cirrhosis or hepatocellular carcinoma in either group. There were no side effects of the entecavir treatment experienced in either group. CONCLUSION: Antiviral therapy with entecavir is effective, safe and well tolerated in CHB virus carriers.
