Stereoselective Synthesis of 1,4-Diols by a Tandem Allylboration–Allenylboration Sequence
作者:Tony S. N. Zhao、Jian Zhao、Kálmán J. Szabó
DOI:10.1021/acs.orglett.5b01048
日期:2015.5.1
that the initial allylboration reaction results in an allenylboronate, which has two stereogenic units: one of them has axial chirality and the other one is a stereogenic carbon center. This reaction proceeds with high diastereoselectivity. The allenylboronate formed in the allylboration reacts with an additional aldehyde with fair to high stereoselectivity depending on the aldehyde substrate. Aromatic
On the Fluorescence Reaction of Pharmaceutically Importanto-Aminobenzamides ando-Aminobenzenesulfonamides with Phthalaldehyde and Analogues
作者:Reinhard Troschütz、Oliver Heinemann
DOI:10.1002/ardp.19953281106
日期:——
In order to develop a specific TLC‐fluorescence detection, drugs such as Quinethazone (1a), Fenquizone (1b), Diazoxide (7), Bendroflumethiazide (11a), Hydrochlorothiazide (11b) and their derivatives were hydrolysed to provide o‐aminobenzamide 2 and o‐aminobenzenesulfonamides 8, 12, and 13. The reaction of these 1,5‐N‐bisnucleophiles with phthalaldehyde (3a) and analogues 3b–e resulted in weak up to
A bisdehydro[14]annuleno[c]furan and a tetrakisdehydro[14]annuleno[14]annulene have been synthesized; their properties and effects of annelation on annulene rings are discussed on the basis of 1H NMR and electronic spectra. Attempts to synthesize the related [14]annuleno[16]annuleno[14]annulene are also described.
A Symmetry-Based Synthesis of the Heterobicyclic Core of the Zaragozic Acids/Squalestatins
作者:Yuzhou Wang、Olga Kataeva、Peter Metz
DOI:10.1002/adsc.200900295
日期:2009.9
furan-3,4-dimethanol (7) using a two-directional route featuring a double asymmetric dihydroxylation. Acidic hydrolysis of the cyclopentylidene acetals of 22 triggered a selective cyclization of the resulting hexaol diketone to generate the 2,8-dioxabicyclo[3.2.1]octane core of the zaragozicacids/squalestatins. Chemoselective oxidative cleavage of a superfluous two-carbon appendage and further functional
Synthesis of porphin analogues containing furan and/or thiophen rings
作者:M. J. Broadhurst、R. Grigg、A. W. Johnson
DOI:10.1039/j39710003681
日期:——
The preparation of 21-oxa, 21-thia-, 21,23-dioxa-, 21,23-dithia-, and 21-oxa-23-thia-porphins is described. These newporphin analogues have spectral properties similar to those of the porphins, which supports their formulation as aromtic macrocycles. Surprising basicity is displayed by 21,22- and 21,23-dioxaporphins and unusual mass spectra are produced by the oxaporphins. Only the 21-oxa- and 21-thia-porphins