Nitrogen-Containing Enediynes

Use of diethynylbenzenes with lysine substituents on the benzene ring or elsewhere results in a synergetic effect for the treatment of tumors. The 

Photochemical conversion of ss-cleavage into double-stand cleavage ----------  

The nine-mem bered aza-enediynes were synthesized via intramolecular N-alkylation, and their reactivity studied [361]. 

-T2 = 19°C For3.787BT, -T2 = 2 C For3.787CT, -T2 =20 C. 

The isoxazolidine-condensed enediynes 3.800 and 3.802 were synthesized by intramolecular [3- -2] cycloaddition of a nitrile oxide to the additional double bond in enediyne 3.799. The structures of the stereoisomeric bicyclic isoxazolidine-fused enediynes 3.800 and 3.801 were fully confirmed by NMR spectroscopy with NOESY 

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Nitrogen-containing 15-membered trialkyne macrocycles, such as l,6,ll-frw(aiylsulfonyl)-l,6,ll-triazacyclopentadeca-3,8,13-triynes and enediynes as 1,6,11-frw(arylsulfonyl)-1,6,11-triazacyclopentadeca-3-ene-8,13-diynes have been prepared and subjected to a [2+2+2]-cyclotrimerization process catalyzed by transition metal complexes, e.g., RhCl(CO)(PPh3)2 <05JOC2033>. The reaction of pemosylated diethylenetriamine and 2-substituted propan-1,3-... 

The total synthesis of (+)-dynemicin A was achieved by S.J. Danishefsky et al. As part of the synthetic studies, highly sensitive enediyne containing quinone imine systems were prepared, and their biological properties were evaluated. The first step in the sequence leading to one such quinone imine began with the oxidation of the nitrogen of the phenanthridine substrate, and the resulting A/-oxide was heated in neat acetic anhydride to induce the Polonovski reaction. 

The 2-(phenylsulfonyl)ethyl carbamate nitrogen-protecting group contained in enediyne 336 (Scheme 7-71) proved to be an important discovery. The facile manner in which it could be removed under mildly basic conditions, even undergoing slow release at physiological pH,... 

Cyclic enediynes containing an ynamino group, such as N-tosyl-4,5-benzoazacyclodeca-2,6-diyne 3.837 exhibit unusual reactivity (Scheme 3.109) [384]. Replacing the propargyl carbon atom in 3,4-benzocyclodeca-l,5-diyne by nitrogen dramatically accelerates the... 

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