Synthesis and characterization of mibolerone

Abstract

Abstract：A simple and effective route for the synthesis of mibolerone was described starting from the estr-5(10)-en-3,17-dione in four steps with the overall yield of 47.0 %. Thus, two methods for key intermediate methylnorandrost were investigated: one(method A) starting from estr-4-en-3,17-dione underwent 3-keto group protected with ethyl orthoformate to give 3-ethoxy-3,5-dien-estr-17-one, the other(method B) from estr-5(10)-en-3,17-dione and protected 3-keto group to give 3,3-dimethoxy-estr-5(10)-7-one in a mild acidic condition. Then, two intermediates were subsequently reacted with methyllithium followed by a mild hydrolytic procedure and gave methylnorandrost with total yield 25.0% and 86.0 %, respectively. In the preparation of 6-dehydrogenation product of methylnorandrost, two procedures(method C and method D) were investigated: one was the protected 17α-methyl-17β-hydroxy ∆ 3,5 -enol ethers estrendiene brominated and the resulting 6-bromo-19-methylnortestosterone was then immediately dehydrohaloenated to give 6-dehydro-19-methylnortestosterone, the total yield only reaches 36.0%; the other was directly dehydrogenated with chloranil and the yield reaches 75.6% under the optimum conditions: in refluxing tetrahydrofuran, the molar ratio of methylnorandrost to chloranil is 0.66 and reaction time of 5 h. The titled compound and intermediates were characterized by 1 H and 13 C NMR, IRMS and elemental analysis.

Chemoradiotherapy enhanced the efficacy of radiotherapy in nasopharyngeal carcinoma patients: a network meta-analysis

“…It was reported that platinum-based concurrent chemoradiotherapy had been accepted by the National Comprehensive Cancer Network as the standard recommendation for locally advanced NPC since the Intergroup 0099 study was published in 1998 [7]. And its superiority in clinical performance over traditional radiotherapy had been demonstrated in subsequent RCT studies [8] and MAs [9, 10].…”

“…As the SUCRA results revealed, therapeutic strategies based on concurrent chemoradiotherapy, including concurrent chemoradiotherapy alone or combined with adjuvant or neoadjuvant chemotherapy, were recommended as the first-line therapies, when the characteristics of individuals are not clarified. It was reported that platinum-based concurrent chemoradiotherapy had been accepted by the National Comprehensive Cancer Network as the standard recommendation for locally advanced NPC since the Intergroup 0099 study was published in 1998 [ 7 ]. And its superiority in clinical performance over traditional radiotherapy had been demonstrated in subsequent RCT studies [ 8 ] and MAs [ 9 , 10 ].…”

Secure joint Bitcoin trading with partially blind fuzzy signatures

“…Specifically, in addition to the participant threshold to be satisfied, a transaction can be successful only if r (< t − 1) privileged participants agree the transaction. In the following, we investigate the joint Bitcoin trading in this scenario and present a variant to cater for the privileged participants included in the threshold (Ghodosi et al 2012;Tang 2007). We first describe the "key generation" procedure.…”

“…It is easy to see that the resulting signature can be unblinded (Tang 2007). In this way, we provide a partially blind multi-signature based-approach so that some privileged participants must be included into the threshold.…”

Improved Thermal Conductivity and Ablation Resistance of Microdiamond‐Modified C/C Composites after Diamond Graphitization

“…[10,11] The intrinsic properties of C/C composites, including the fiber architecture, matrix microstructure, and bulk density, are closely concerned with the ablation property of the composites. [12][13][14] Carbon fibers and various kinds of carbon matrices (pitch carbon, resin carbon, and pyrolytic carbon [PyC]) exhibit different ablation properties considering their different microstructures. C/C composites with a high graphitization degree and density usually possess better ablation resistance due to the reduced reactive sites and diffusion paths for oxidation gases.…”