1,4-Benzodiazepin-2-ones, synthesis

I, 5-benzodiazepines one-pot microwave-assisted synthesis and evaluation for antioxidant activity and lipid peroxidation inhibition,... 

The benzodiazepine nucleus is extremely important, as it is the base of several drugs and other biologically active compounds with different properties. A facile synthesis of 2-methyl-l,4-benzodiazepin-5-ones has been described by Santagada and co-workers [162]. Isatoic anhydride 254 was reacted with M-substituted allylamines under microwave irradiation to give compound 255... 

Microwave-promoted reactions continue to extend their reach in heterocyclic synthesis. Regioselective N4-aminoethylation of the l,4-benzodiazepin-2-one 94 was observed under microwave conditions in DMF/K2C03 to afford, for example, 96a and 96b in 64% and 67% yield respectively (Table 4). In contrast, the thermal reaction at 80 °C in DMF with K.2CC)3 as base gave the Nl-aminoethylation products (95a, 65%) and (95b, 76%). These results were... 

Scheme 3.5 Synthesis of 1,4-benzodiazepin-2-ones (83) by cyclative cleavage [172].

One of the first cross-coupling reactions performed on solid supports was the Stille reaction [250] which is a paUadium-catalyzed reaction of a trialkylaryl or trialkylalkenyl stannane with an aromatic iodide, bromide or triflate. In contrast to the process in liquid-phase, the organotin reagent is easily removed from the solid-phase because of the subsequent washing processes. Immobilized aryl halides have been frequently coupled with aryl and alkenylstannanes, whereas stan-nanes attached to the solid support have been used less frequently for the StiUe reaction. An example is the synthesis of a benzodiazepine library by EUman et al. Recently, a Stille cross-couphng reaction has been employed in the synthesis of al-kenyldiarylmethanes (ADAM) series of non-nucleoside HlV-1 Reverse Transcriptase Inhibitors (Scheme 3.14) [251]. 

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