The Chemistry and Biology of Nakiterpiosin – C-nor-D-Homosteroids

Abstract

Isolated from the sponge Terpios hoshinota that causes coral black disease, nakiterpiosin was the first C-nor-D-homosteroid discovered from a marine source. We provide in this account an overview of the chemistry and biology of this natural product. We also include a short history of the synthesis of C-nor-D-homosteroids and the results of some unpublished biological studies of nakiterpiosin.

A New Synthesis of 3‐(Sulfonamido)benzofurans through an Acid‐Promoted Cascade Reaction of N‐(2,2‐Dichloro‐2‐phenylethylidene)arenesulfonamides with para‐Substituted Phenols

“…The reaction is likely to be applied with a range of polyhalogenated imines so that the substituent at position 2 of the annulated furan ring can be varied. The method presented herein and the known three‐component approach9 to benzofurans with similar structures, complement each other. The latter method9 allows 2‐aryl‐3‐(sulfonamido)benzofurans to be generated that are either unsubstituted or that include bulky substituents; however, these approaches require the use of more expensive reagents and catalysts (arylglyoxals, indium or hafnium salts) 9…”

“…Synthetic approaches to 3‐amino‐ and 3‐amido‐substituted benzofurans are based on the reactions of ortho ‐hydroxybenzonitriles 7. Three‐component reactions of acetylenes with ortho ‐hydroxybenzaldehydes and amines in the presence of copper salts8 or arylglyoxals, phenols and para ‐toluenesulfonamide, in the presence of Hf(OTf) 4 , TiCl 4 , or InCl 3 are also known 9. In addition, the synthesis of 2,3‐bis(arylamino)benzofurans by reaction of 2‐[(arylimino)methyl]phenols with aryl isocyanides catalyzed by BF 3 has been reported 10.…”

Acid/Base Switching of the Tautomerism and Conformation of a Dioxoporphyrin for Integrated Binary Subtraction

“…In spite of the mild reaction conditions and the satisfactory yield, the high toxicity of thallium urged us to explore alternative synthetic routes. Thus, PDPH 22 was first complexed with zinc(II) to afford ZnPDPH 02 , which could then be oxidized to ZnDPH 02 with anhydrous FeCl 3 [12] in DMF heated to reflux. Demetallation of ZnDPH 02 with H 2 SO 4 gave DPH 22 in an overall yield of approximately 35 %.…”

“…[10c] The Zn 2 + complex of DPH 22 was also successfully crystallized from DMF. For ZnDPH 02 ·3 DMF (Figure 2 c), phenolic CÀO single bonds are present with the bond lengths [12] of 1.364 (5) and 1.385 (5) , respectively. This finding indicates that planar DPH 22 can coordinate as a dianionic ligand with two NH moieties coordinated in their deprotonated form.…”

Preparation and Characterization of Metronidazole-Surface Imprinted Microspheres MIP-PSSS/CPVA for Colon-Specific Drug Delivery System

“…Besides, there are still some prodrug forms (13,14). OCCDS can be used not only to treat colon cancer (15,16), colitis (17,18) and circadian rhythm diseases (19), but also to improve the bioavailability of protein and peptide drugs (20).…”