Synthesis of thiopyrano[4″,3″:4′,5′]pyrido[3′,2′:4,5]furo[3,2-d]pyrimidines

<正>Reactions of the 6-hydroxy-thiopyrano[3,4-c]pyridine-5-carbonitrile derivative 1 withα-halo-carbonyl compounds gave the ortho-substituted intermediates 2a-c which were converted into furo[2,3-b]thiopyrano[4,3-d]pyridines 3a-c by fusion of a furan moiety under basic conditions.Further cyclization of 3a-c led to a fusion of a pyrimidine ring,yielding the tetracyclic products 6,7 and 8.In addition,condensation of 6 with various aromatic aldehydes afforded the corresponding imines 9a,b.Mannich reaction of 7 gave products 10a,b.     

Synthesis of Hexa- and Octahydropyrido[3'2':4,5]thieno[3,2-d]pyrimidines

The reaction of N-methylmorpholinium 4-(2-chlorophenyl)-5-cyano-2-oxo-1,2,3,4-tetrahydropyridine-6-thiolate with chloroacetamide in DMF in the presence of an excess of KOH gave 3-amino-2-carbamoyl-4-(2-chlorophenyl)-6-oxo-4,5,6,7-tetrahydrothieno[2,3-b]pyridine. Refluxing the latter with acyl chlorides in AcOH or heating in formic acid gave hexahydropyrido[3',2':4,5]thieno[3,2-d]pyrimidine derivatives and reaction with cyclohexanone gave a spiro-linked octahydropyrido[3',2':4,5]thieno[3,2-d]pyrimidine.     

2',5'-二氢-1'H-吡咯骈[3',4':1,2][60]富勒烯衍生物的合成

以甘氨酸乙酯盐酸与取代的苯甲醛为原料,制得了一系列亚胺,然后用亚胺与C~6~0反应,得到带有不同取代基的吡咯烷骈[60]富勒烯衍生物.经^1HNMR,^1^3CNMR,FT-IR,UV-vis以及TOF-SMS等方法对所得化合物结构进行了表征,并进行了产物的生物活性测试。     

Synthesis and antimicrobial activity of new derivatives of pyrano[4',3':4',5']pyrido[3',2':4,5]thieno[3,2-d]pyrimidine and new heterocyclic systems

Taking into account previously obtained biological results on some polyheterocyclic compounds (containing different heteroatoms) and in particular on several 8-amino-5-isopropyl-2,2-dimethyl-10-(methylthio)-1,4-dihydro-2H-pyrano[4’’,3’’:4’,5’]pyrido[3’,2’:4,5]thieno[3,2-d]pyrimidines Ia-v we have carried out the synthesis of twentyone 8-amino-5-isobutyl-2,2-dimethyl-10-(methylthio)-1,4-dihydro-2H-pyrano[4’’,3’’:4’,5’]pyrido[3’,2’:4,5]thieno[3,2-d]pyrimidines 6. Therefore we have slightly modified the structure of the previously studied I introducing at C-5 an isobutyl group instead of the previously examined isopropyl ones in order to see if this variation (changing a little the lipophilicity) will affect the biological activity. Furthermore thieno[3,2-d]pyrimidine-8-thione 7 and their S-alkylated 8 were synthesized. Finally by alkylation of 5-isobutyl-2,2-dimethyl-10-thioxo-1,4,10,11-tetrahydro-2H-pyrano[4'',3'':4',5']pyrido[3',2':4,5]thieno[3,2-d]pyrimidin-8(9H)-one 3 with alkyl dichlorides (bifunctional reagents) we realized the cyclization of a thiazole or thiazine ring on the [b] side of the pyrimidine ring with formation of the new condensed pentaheterocyclic systems: pyrano[4'',3'':4',5']pyrido[3',2':4,5]thieno[3,2-d][1,3]thiazolo[3,2-a]pyrimidin-8-one 11 and pyrano[4''',3''':4'',5'']pyrido[3'',2'':4',5']thieno[3',2':4,5]pyrimido[2,1-b][1,3]thiazin-8-one 12. It was found that some of the synthesized compounds showed interesting antimicrobial activity (by agar diffusion method) against some gram-positive and gram-negative bacilli strains.     

An efficient method for the synthesis of thieno[3',2':2,3]pyrido-[4,5-d]-thiazolo[3,2-a]pyrimidinones

An efficient method for the preparation of thieno[3',2':2,3]pyrido[4,5-d]thiazolo[3,2-a] pyrimidin-5-ones 5 is described. The key intermediate, 7-(3-amino-4-cyano-5-phenyl aminothieno-2-yl)-5H-thiazolo-[80_TD$IF]3,2-a]pyrimidin-5-one(3), was synthesized from 7-chloromethyl-5H-thiazolo[3,2-a]pyrimidin-5-one(1)with potassium-(2,2-dicyano-1-phenylaminoethen-1-yl)thiolate(2) by Thorpe–Ziegler isomerization.Subsequent reaction of the intermediate amine with aromatic aldehydes via Pictet–Spengler reaction provided thieno-pyridine fused thiazolo[3,2-a]pyrimidines under p-Ts OH as catalyst in good yields.     

Planar beta-linked oligothiophenes based on thieno[3,2-b]thiophene and dithieno[3,2-b:2',3'-d]thiophene fused units

A series of planar beta-linked oligothiophenes based on thieno[3,2-b]thiophene and dithieno[3,2-b:2',3'-d]thiophene fused units were synthesized. The optical data indicate a blue shift of the absorption maximum in comparison to the alpha-linked analogues due to cross-conjugation between fused rings. The crystal structures of 3,3'-bi(thieno[3,2-b]thiophene) and 3,3';6',3"-ter(thieno-[3,2-b]thiophene) reveal edge-to-face pi-stacked dimer motifs, whereas the crystal structure of 3,3'-bis(dithieno[3,2-b:2',3'-d]thiophene) consists of face-to-face pi-stacked molecules. [structure: see text]     

Structure of photochromic l',3', 3'-trimethyl-6-nitro-8-bromospiro (4-azaindoline-2,2'-[2h-1]benzopyran)

Conclusions An x-ray diffraction structural analysis of photochromic 1'-3',3'-trimethyl-6-nitro-8-bromospiro (4-azaindoline-2,2'-t2H-l]benzopyran) showed that azaindoline and indoline spiropryans have similar structures, in which the C_spiro-O bond cleaved upon photoexcitation is elongated and weakened.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2593–2595, November, 1986.     

Photoreactions of 1-acetylisatin with alkynes: regioselectivity in oxetene formation and easy access to 3-alkylideneoxindoles and dispiro[oxindole[3,2']furan[3',3' ']oxindole]s

[reaction: see text] Photoinduced reactions of 1-acetylisatin (IS) with diphenylacetylenes 1a-c, 1-(p-methoxyphenyl)propyne 2, and 1,4-diphenyl-1,3-butadiyne 3 gave beta,beta-disubstituted 3-alkylidene oxindoles 6-12 respectively via [2+2] cycloaddition of 3IS* with the alkyne and subsequent oxetene ring opening. Photoreactions of IS with phenylacetylenes 4a-d and cyclopropylacetylene 5 furnished the dispiroindole[3,2']furan[3',3' ']indoles 13 and 14. Compounds 13 and 14 are formed in tandem reactions initiated by [2+2] cycloaddition of 3IS* with the alkynes to give spirooxetenes Va and Vb, which upon spontaneous ring opening gave the alpha,beta-unsaturated aldehydes IVa and IVb. It is proposed that hydrogen abstraction of 3IS* from the C(O)-H functionality in IV followed by dissociation of the triplet isatin ketyl (A)-aldehyde acyl (B) radical pair and an oxygenphilic attack of the acyl radical B at the C3 carbonyl oxygen atom of a neutral IS gave the 2:1 (IS:4) radical C, which took part in an intramolecular radical cyclization to give the dispiroindole[3,2']furan[3',3' ']indoles 13 and 14. The regioselectivity in the [2+2] photocycloadditions of IS with 4 to afford the oxetene Va depends on the intervening of the more stable 1,4-diradical intermediates VI, which have a linear alpha-phenyl-substituted vinyl radical where the phenyl provides spin delocalization of the radical center at the sp carbon atom.     

Synthesis of (2S,3R)-[3',3',3'-2H3]-valine and (2S,3S)-4-fluorovaline

A new synthesis of (2S,3R)-[3',3',3'-2H3]-valine has been completed and (2S,3S)-4-fluorovaline has been synthesised for the first time. Both compounds have been prepared by routes involving stereoselective addition to the (S)-pyroglutamate derivative and are available for studies in several areas of bio-organic chemistry.