RESUMO
Formal homo-Nazarov cyclization of benzonorcaradienes produced by intramolecular hydroarylation of arylated alkynylcyclopropanes promoted by TfOH has been described, providing stereoselective access to highly substituted hydrochrysenes. An unprecedented 1,2-acyl migration occurred for the 2-heteroaroyl substrates, thus giving the same products as their 3-heteroaroyl analogs. Moreover, these products could be readily oxidized by air to fully π-conjugated chrysenes after decarboxylation.
RESUMO
BACKGROUND: This study aims to assess current evidence of ultrasound in diagnosis of hydatidiform mole (HM) in early pregnancy (EP). METHODS: This study will incorporate case-control study on investigating the impact of ultrasound in diagnosis of HM in EP. Potential articles will be retrieved in electronic databases of Cochrane Library, MEDLINE/PUBMED, EMBASE, PsycINFO, WANGFANG, and CNKI from inception to the present. Conference proceeding, website of clinical trial registry, and reference list of key articles will be examined for additional studies. Two independent researchers will scan and select studies, collect and manage data, and appraise methodological quality of all eligible studies. We will carry out summary effect size, statistical heterogeneity, synthesize, and analyze outcome data. RESULTS: This study will summarize present evidence to assess the accuracy of ultrasound in diagnosis of HM in EP. CONCLUSION: This study may provide evidence for ultrasound in diagnosis of HM in EP, which may benefit both patients and clinicians. STUDY REGISTRATION: INPLASY202080080.
