L- -quinazolinone

The above two quinazolinones were prepared as intermediates in the synthesis of the chiral nonnucleoside reverse transcriptase inhibitor DPC 961 441, although compounds of this type can also be formed directly by the addition of lithium cyclopropylacetylide to the N-unsubstituted 2(l//)-quinazolinone 440, in the presence of a chiral alkoxide moderator <20000L3119, 2004JA5427>. 

Naphtho[2, 3 3,4]-[l,2,5]triazocino[8,l+]quinazolinone 137 was obtained by refluxing of 2-substituted 3-amino-quizalin-4-one with 2,3-dichloro-l,4-naphthoquinone in DMF (Scheme 35 <2001MOL267>). Initial formation of 5,6-dihydrotriazocine derivative was followed by elimination of arylsulfinic acid and formation of ring system 137. 

Known pyrrolo[2,l-/)]quinazoline and pyrido[2,l-/>]quinazolinone alkaloids are named and depicted in Table II. 

The pyrido[2,l- )]quinazolinone 286 could be produced in about 20% yield by simply boiling a solution of benzisothiazolinone (296) in aqueous pyridine for 6 hr. Pyrido[2,l- ]quinazolinone (286) formation can be interpreted by a mechanism in which nucleophilic attack of the pyridine nitrogen atom occurs on the carbonyl group of benzisothiazolinone (296). 

Suschitzky and co-workers hydrogenated the lactam 305 over palladium on charcoal under pressure in the presence of 1 molar equivalent of hydrochloric acid in ethanol at room temperature and observed the formation of the azepino[2, l- )]quinazolinone 306 and its iV-oxide 307 in yields of 12 and 69%, respectively. 

Spath and KuflFner °° obtained the tetrahydropyrido[2, l- )]quinazolinone 203 when the pyrido[2,1 - >]quinazolinone 286 was hydrogenated over palladium on carbon in acetic acid. By means of hydrogenation in ethanol for 4 days, Paterson et prepared the hexahydropyrido[2,l- )]quinazolinone 102. 

Bemath, Fiilop and co-workers " - " studied the reduction of compounds of types 224 and 225. On reduction with sodium borohydride in methanol or by hydrogenation over platinum oxide in ethanol or acetic acid, the m 5-decahydropyrido[2, l- )]quinazolinone 341 and its quaternary derivative 342 gave exclusively the perhydro derivative 343. - °... 

Reduction of the azepino[2, l- )]quinazolinone 348 with sodium borohy-dride in methanol led to the ring-opened product 349 at ambient temperature and to the azepino[2,l- >]quinazolinone 350 at — 20°C. ... 

Oxidation of the dihydropyrido[2,l- ]quinazolinones 360 with chloranil afforded the pyrido[2,l-/>]quinazolinones 361. ... 

With potassium permanganate under basic or neutral conditions, the pyrido[2,l- )]quinazolinone 286 and its 8-nitro derivative 364 yielded the quinazolin(3//)-4-one, while in acidic medium the product was the 2,4-dioxo-1,2,3,4-tetrahydroquinazoline. 

The alkylation of the hexahydropyrido[2,l- >]quinazolinone (102) with coaminoalkyl chloride in dimethylformamide in the presence of sodium hydride and the reaction of the perhydropyrido[2,1 -6]quinazolinones 343 (R = H) and 346 (R = H) with methyl iodide in acetone in the presence of silver oxide " - led to products alkylated on the nonbridgehead nitrogen atom. 

The 2-cyanopyrido[2,l- )]quinazolinone 437 was prepared from the 2-bromo derivative 436 with cuprous chloride in l-methyl-2-pyrrolidinone at 180°C.22 ... 

Reaction of 7V-(2-aminophenyl)-3,6-dichloro-4-pyridazinecarboxamide (61) with base did not give the expected pyridazino[3,4- ][l,5]benzodiazepine derivative but instead gave 3-(5-chloro-3-pyrazolyl)-2(l//)-quinazolinone (62) (Scheme 12) via reaction at C-4 rather than C-3 <94H(38)2081>. 

The derivatives of 4(l)-quinazolinone 138 are formed with yields hydrochlorides are boiled with the anhydrides 140 in pyridine [79],... 

The reaction of 3-amino-2-thioxo-4(l//)-quinazolinone or its methylthio derivative 96 with hydrazonoyl halides 95, in the presence of ethanol and triethylamine afforded 6W-1,2,4,5-tetrazino[3,2-b]quinazolin-6-ones 97 <01M959>. 

Substituted imidazo/benzimidazo[2,l- ]quinazolinones could be synthesized from (l//-imidazol-l-yl)[2-(alkylamino)phenyl]methanones and (l//-benzimidazol-l-yl)[2-(alkylamino)phenyl]-methanones catalyzed by CuCl in the absence of hgand using air as the oxidant (Scheme 8.105). The method is tolerant toward functional groups in the substrates, and a range of 5-substituted imidazo/benzimidazo[2,l- ]quinazolinones could be obtained in moderate to good yields. A C(sp )-H bond was activated to form a new C-N bond [179]. 

---