Pyrido quinazoline

The lipophilicity (7 m value) and specific hydrophobic surface area of 1 ]/f-pyrido[2,]-fi]quinazolin-] 1-one and its isomeric 6//-pyrido[l, 2-u]qui-nazolin-6-one were determined by reversed-phase thin-layer chromatography (98MI4). 

Bond orders, charges on the atoms in 1 l//-pyrido[2,l-Z)]quinazolin-l 1-one and its protonated form were calculated by quantum chemical calculations by the semiempirical AMI method. According to the results, the equilibrium conformation of the ring in 1 l//-pyrido[2,l-Z)]quinazolin-l 1-one is planar, while l//-pyrimido[l,2-u]quinolin-1-one adopts a conformation close to a half-chair due to the unfavorable interactions between the oxygen atom of the carbonyl group and the ring C-10 atom in the pen-position (97MI22). 

IR Spectra of the hydrochloride of 6,7,8,9-tetrahydro-l l//-pyrido[2,l-Z)]quinazolines and their ZnCli complexes were investigated in the stretching vibration region of N" " (2000-3500 cm ) (97MI18, 99MI25). 

The structures of 5-ethyl-1 ]-methyl-9-oxo-5,l l-dihydro-9/7-pyrido[2,1-6]-quinazohne-8-carboxylic acid (00K669), the chromophore 4 of isopyoverdin siderophores (01T1019), and that of 5,5n,6,7,8,9-hexahydro-l l//-pyrido [2,]-6]quinazoline (99SL1383) were justified by X-ray analysis. 

Condensation of 6,7,8,9-tetrahydro-l]/f-pyrido[2,]-6]quinazolin-ll-one and PhCHO in boiling AC2O for 48 h yielded a 6-phenylmethylene derivative (01H(55)1555). 

A-Substituted 11-oxo-l l//-pyrido[2,l-6]quinazoline-6-carboxamides were prepared from 11-oxo-l l//-pyrido[2,l-6]quinazoline-6-carboxylic acids and amines in the presence of (/-Pr)2EtN and benzotriazol-l-yloxytris(dimethy-lamino)phosphonium hexafluorophosphate in CH2CI2 (98MIP1, 98MIP2, 99USP5908840, 99USP5914327). 

Cyclization of 2-(4-hydroxypentyl)quinazolin-4(3//)-ones 422 under Mitsunobu s conditions afforded only linearly fused 6,7,8,9-tetrahydro-1 l/f-pyrido[2,l-6]quinazolin-l l-ones 423 without angularly fused 1,2,3,4-tetrahydro-6//-pyrido[l, 2-n]quinazolin-6-ones 424 (98CPB928). 

Oxidative cyclization of 1 -[(2 -aminocarbonyl)phenyl]piperidine and its 4 -substituted derivatives with Hg(OAc)2-EDTA reagent afforded 1,2,3,4-tet-rahydro-6//-pyrido[2,l-Z)]quinazolin-6-one and its 3-substituted derivatives in 36-82% yields (99ZN(B)1577). Similarly, ( )-2-(piperidin-2-yl)benzal-doximes gave 2,3,4,4u-tetrahydro-l//-pyrido[l,2-u]quinazolin-5-oxide and... 

The reaction of methyl anthranilate and 3-amino-2-chloropyridine in 1,2,4-trichlorobenzene in the presence of KOt-Bu at 50 °C gave 5,1 l-dihydro-6//-pyrido[2,3-Z)]benzodiazepin-6-one and 6-amino-ll//-pyr-ido[2,l-Z)]quinazolin-l 1-one as a by-product (99BMCL3031). 

Reaction of 2-amino-3-hydroxypyridine and cyclohexanone 433 in boiling AcOH yielded N, 1 -diphenyl-6-hydroxy-3-methyl-11 -0x0-1,2-dihydro-11 //-pyrido[2,l-Z)]quinazoline-2-carboxamide (434) (98MI2, 99USP5908840, 99USP5914327). 

Reaction of 1 -methylene-1,2,3,4-tetrahydro-5//-pyrazino[2,1 -Z)]quina-zoline-3,6-diones (435) with PhLi and MeMgBr in THE at —78°C gave a mixture of 1 l//-pyrido[2,l-Z)]-quinazolin-l 1-ones 435-439 (01T1987). 

The use of 1 l//-pyrido[2,l-Z)]quinazolin-l 1-ones in an organic electroluminescent device was patented (99JAP(K)99/74080). 2//-Pyrimido[2,l-n]isoquinolin-7-ols were patented as multi-functional fuel and lube additives (97USP5646098). 

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