Thiolactones, macrocyclic

In the event, macrocyclic bis(thiolactones) perform admirably in the macrocycle-to-bicycle bridging reaction (see Scheme 5).17 For example, the eis-fused tetracycle 25 can be produced, in 80%... 

Scheme 5. Bridging macrocycles to form bicycles the first successful experiments with bis(thiolactone) 24. The terms bis(thiolactone) and dithiolactone are used in this chapter to describe compounds of type 24 even though such systems are sometimes referred to as dithionolactones or dithioxolactones.

The productive transformation of a macrocycle to a bicycle can also be executed simply by irradiating a bis(thiolactone). For example, irradiation of a solution of bis(thiolactone) 24 in toluene for... 

Macrocyclic 14-membered lactams, lactones, and thiolactones 211 have also been prepared from 3-amino-l,2,5-thiadiazole-4-carboxylic acids 210 (Equation 47) <1996CHE975>. 

Stannyl thiolates were recently shown to be applicable to the formation of the macrocyclic poly-thiolactones (23) and (24), according to equation (16). ... 

Iminium salts, generated in situ from the amides and lactams, react with 1 to produce the corresponding thioamides and thio-lactams, respectively, in good yields (eq T)P- The advantages of this methodology are the easy work-up and chemoselectively amides are thionated in the presence of ketones, aldehydes, and esters (eq 8). ra-Halo acid chlorides react with 1 and the corresponding thiolactones are obtained in moderate yields under mild reaction conditions (eq 9). This reaction works well for the synthesis of small and medium ring thiolactones, but is not useful for the synthesis of macrocyclic thiolactones. ... 

This chapter is devoted to a biologically active macrocyclic compound 1, which is neither a dmg molecule that has been introduced into therapy nor was its stereochemistry created by a synthetic chemist. Compound 1 is both a cyclic polypeptide and a macrocyclic thiolactone at the same time. 

Thiolactones can be quantitatively inserted in the Sn-0 bond of Sn-contain-ing macrocycles [71,75,81,82] since the Sn-S bond is more stable than Sn-0 (Scheme 65) [75]. 

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