Synthesis of 1-(2,2-Dimethylpropyl)-Cyclopropene (1-DCP) as an Ethylene Antagonist.

Ethylene is a gaseous hydrocarbon molecule known as a plant hormone that promotes fruit ripening and senescence. Efficiently controlling ethylene is a central key to maintaining the quality of agricultural products. The current study uncovered a synthetic method for 1-(2,2-dimethylpropyl)-cyclopropene (1-DCP) as a cyclopropene derivative to inhibit ethylene action in fruit ripening and senescence. We synthesized 1-DCP using α-diisobutylene through a two-step process, including allylic chlorination by hypochlorite and HCl, followed by α-elimination of the allylic chloride using a strong base, lithium diethylamide. GC-MS and NMR analyses demonstrated that 1-DCP was synthesized efficiently with 35% yield and 95% purity. When treated as an aqueous emulsion on plants, including persimmon and banana fruits, 1 mM 1-DCP showed effective inhibition of ethylene action by delaying the flesh softening and peel degreening, which are representative phenomena of fruit ripening and senescence induced by ethylene. Our data demonstrated that 1-DCP could be synthesized and used as a sprayable ethylene antagonist for pre- or post-harvest growth regulation in plants and fruits.

[Incidence of gallbladder stones in renal transplant recipients].

BACKGROUND/AIMS: Gallbladder stone is one of the major cause of morbidity in adults. Renal transplantation has been found to increase the risk of gallbladder stone formation. The real incidence of gallbladder stones in renal transplant recipients is not exactly known. We performed this study to identify the risk factors for cholecystolithiasis. METHODS: We compared the prevalence of gallbladder stone in 222 renal transplantation patients with that in 222 age and sex matched controls. Patients who had chronic liver disease, renal disease, and diabetes were excluded from the control group. RESULTS: In our study, the incidence of gallbladder stones is 8.6% (19/222 patients) in renal transplantation patients, which was significantly higher than 3.60% (8/222 control) in the control group (p=0.029). In the most of our renal transplantation patients, cholecystolithiasis was asymptomatic. We did not find a difference in age, sex, duration after transplantation, causes of renal failure, resistance index between patients with and without gallbladder stones in renal transplantation patients. CONCLUSIONS: Our results suggest that the incidence of gallbladder stones is higher in renal transplant recipients than non-transplant population in Korea. Further studies will be needed to focus the factors contributing to the gallbladder stone formation after renal transplantation, especially in regard to immunosuppressive drugs.