59276-34-5Relevant articles and documents
Structurally Simple Benzylidene-Type Photolabile Diol Protecting Groups
Ding, Xiong,Devalankar, Dattatray A.,Wang, Pengfei
, p. 5396 - 5399 (2016/11/06)
Two structurally simple photolabile protecting groups for releasing 1,2- and 1,3-diols have been developed. The diols can be protected in high yields and released from their corresponding acetals with high chemical efficiency.
Ion pairing effects on the regioselectivity of arylic versus benzylic C-O bond reductive cleavage: synthetic applications
Azzena, Ugo,Dettori, Giovanna,Mascia, Ilaria,Pisano, Luisa,Pittalis, Mario
, p. 11998 - 12006 (2008/03/14)
The regioselectivity of the reductive cleavage of 3,4,5-trimethoxybenzyl methyl ether strongly depends on the alkali metal employed as a reducing agent and solvent effects. Reactions run using Na as a reducing agent led to aromatic C(4)-O bond cleavage, whilst reductions run in the presence of Na/15-crown-5, or using Li as a reducing agent, led to highly regioselective benzylic C-O bond cleavage. This regioselectivity turnaround is discussed in terms of major solvent effects affecting the fragmentation paths of a common reaction intermediate. Synthetic applications of these findings led to the synthesis of biologically active compounds, like 2,5-dialkyl-substituted resorcinols, or 1-(3,4,5-trimethoxyphenyl)-2-arylethanes structurally related to combretastatin.
Synthesis and complement inhibitory activity of B/C/D-Ring analogues of the fungal metabolite 6,7-diformyl-3′,4′,4a′,5′,6′,7′,8 ′,8a′-octahydro-4,6′,7′-trihydroxy-2′, 5′,5′,8a′-tetramethylspiro[1′(2′H)- naphthalene-2(3H)-benzofuran]
Bradbury, Barton J.,Bartyzel, Piotr,Kaufman, Teodoro S.,Nieto, Marcelo J.,Sindelar, Robert D.,Scesney, Susanne M.,Gaumond, Bruce R.,Marsh Jr., Henry C.
, p. 2697 - 2705 (2007/10/03)
This paper reports the synthesis and the bioassay of 4-methoxy- and 4-hydroxyspiro[benzofuran2(3H)-cyclohexane] partial analogues (5) of the complement inhibitory sesquiterpene fungal metabolite 6,7-diformyl-3′,4′,4a′,5′,6′,7′, 8′,8a′-octahydro-4,6′,7′-trihydroxy-2′, 5′,5′,8a′-tetramethylspiro[1′(2′H)- naphthalene-2 (3H)-benzofuran] (1a, K-76) and its silver oxide oxidized product (lb, K-76COOH). The described target compounds represent spirobenzofuran B/C/D-ring analogues lacking the A-ring component of the prototype structure. The target compounds were evaluated by the inhibition of total hemolytic complement activity in human serum. It was observed that the structurally simplified analogue 4-methoxyspiro[benzofuran-2(3H)cyclohexane]-6-carboxylic acid (5a) exhibited an IC50 = 0.53 mM similar to the IC50 = 0.57 mM that was observed for the natural product derivative 1b. Exhibiting an IC50 = 0.16 mM, the three-ringed partial structure 6-carboxy-7-formyl-4-methoxyspiro[benzofuran-2(3H)-cyclohexane] (5k)was found to be the most potent target compound. Like the natural product, 5k appears to inhibit primarily at the C5 activation step and inhibits both the classical and alternative human complement pathways. Several other analogues inhibited complement activation in vitro at concentrations similar to those required for inhibition by the natural product 1b.
