新型芳醛并苯甲酰腙类化合物的合成及其抗结核活性

以2-氨基-5-取代苯甲酸甲酯或2-氨基-5-哌啶基苯磺酰胺为起始原料,经酰化、胺基化、肼解和缩合反应合成了10个新型的芳醛并苯甲酰腙类化合物(8a~8i或Ⅳ),其结构经1H NMR和ESI-MS表征。初步研究了8a~8i和Ⅳ的抗结核活性。结果表明:8c对结核分枝杆菌H37Rv和草分枝杆菌1180的MIC分别为9μg·m L-1和11μg·m L-1,与阳性对照药异烟肼(7μg·m L-1和8μg·m L-1)和利福平(8μg·m L-1和10μg·m L-1)的抑制活性相当。     

新型2-取代苄基硫代嘧啶衍生物的合成及其细胞毒性

以乙酰乙酸乙酯和硫脲为起始原料,经环合、取代、氯代和亲核取代反应合成了16个新型的2-取代苄基硫代嘧啶衍生物(7a~7p),其结构经1H NMR,13C NMR和HR-MS表征。细胞毒性测试结果表明:6-甲基-4-对氯苯胺-2-苄基硫代嘧啶(7b)和6-甲基-4-对溴苯胺-2-苄基硫代嘧啶(7c)对MGC-803(人胃癌细胞)具有较好的抑制活性,其IC50分别为3.126μg·m L-1和2.197μg·m L-1,优于5-氟尿嘧啶(IC503.208μg·m L-1)。     

新型酰基脲类Raf激酶抑制剂的合成及其抗肿瘤活性

以4-氯吡啶甲酸为原料,经6步反应制得两个中间体——取代基-4-【{2-[5-(三氟甲基)-1H-咪唑-2-基]吡啶-4-基}氧基】苯胺(7a和7d);7分别与取代苯甲酰基异硫氰酸酯反应,合成了6个新型的酰基脲类Raf激酶抑制剂(9a~9f),其结构经1H NMR和ESI-MS表征。用MTT法考察了9a~9f对人胃癌细胞株(BGC823)的抑制活性。结果表明:N-【3-氟-4-{2-[5-(三氟甲基)-1H-咪唑-2-基]吡啶-4-氧基}苯基】-4-氯苯甲酰硫脲(9c)和N-【4-{2-[5-(三氟甲基)-1H-咪唑-2-基]吡啶-4-氧基}苯基】-3-(吡啶-3-基)丙烯酰硫脲(9d)的抑制活性较好。在用药量为100μg时,9c和9d对BGC823的抑制率分别为66.86%和63.60%,与索拉非尼药效接近(70.97%)。     

新型苯甲酰胺类HDAC抑制剂的合成及其抗肿瘤活性

以MS-275为先导化合物,设计并合成了7个新型苯甲酰胺类化合物(6a~6c,14a,14b,15a和18),其结构经1H NMR和ESI-MS表征。采用MTT法测定了6a~6c,14a,14b,15a和18对人急性白血病细胞(HL60)和人乳腺癌细胞(MCF-7)的体外抗肿瘤细胞增殖活性。结果表明:N-(2-氨基苯)-3-[4-(吡啶-3-基)嘧啶-2-氨基]己酰胺(6a),N-(2-氨基苯)-4-【3-{4-[(二乙胺基)甲基]苯基}丙烯酰】苯甲酰胺(14a)和N-(2-氨基苯)-4-[3-(吡啶-3-基)丙烯酰]丙酰胺(18)的抑制活性较好,其GI50依次为5.72μmol·L~(-1),6.91μmol·L-1,7.11μmol·L~(-1)和3.46μmol·L~(-1),4.12μmol·L~(-1),3.97μmol·L~(-1),优于MS-275(7.88μmol·L-1和4.49μmol·L~(-1))。     

新型苯并咪唑衍生物的合成及其抗凝血活性

以3-[(3-氨基-4-甲基氨基苯甲酰)吡啶-2-基氨基]丙酸乙酯为原料,与4-氰基-3-氟苯取代基乙酸经环化反应制得3-【【2-{[(4-氰基-3-氟苯取代基)甲基]-1-甲基-1H-苯并咪唑-5-基}羰基】吡啶-2-基】氨基丙酸乙酯(3a,3e);3经水解和酰胺化反应制得3-【【【2-{[(4-氰基-3-氟苯基)取代基]甲基}-1-甲基-1H-苯并咪唑-5-基】羰基】吡啶-2-基氨基】丙酰取代胺基(6a~6h);6与乙酰氧肟酸经环合反应合成了8个新型的苯并咪唑衍生物(7a~7h),其结构经1H NMR和HR-ESI-MS表征。抗凝血活性结果表明:7a和7c的抗凝血活性最好,其a PTT值分别为(83.1±4.2)s和(80.7±2.9)s,优于阳性对照药达比加群酯(75.3±2.1)s。     

新型吡唑甲酰胺类化合物的合成及其抗肿瘤活性

以2-氰基乙酰胺为起始原料,与三乙氧基取代化合物经加成反应制得取代烯酰胺类化合物(3a~3c);3a~3c与芳肼经环合反应得取代吡唑-4-甲酰胺类化合物(5a~5d);5a~5d与酰氯经酰化反应合成了6个新型的1-芳基-3-取代-5-取代氨基-4-吡唑甲酰胺类化合物(7a~7f),其结构经1H NMR,MS和元素分析表征。抗肿瘤活性测试结果表明,7a~7f对人乳腺癌细胞(A)、人宫颈癌细胞(B)和人肝癌细胞(C)有一定抑制作用,其中3-甲基-5-[4-(甲磺酰胺基)苯甲酰胺]-1-苯基-1H-吡唑-4-甲酰胺(7f)的抑制活性最好,对A,B和C的IC50分别为3.25μM,8.74μM和10.47μM。     

新型哌啶噻唑类化合物的合成及杀虫活性

为了探寻新型的生物活性化合物,设计并合成了12个未见文献报道的新型哌啶噻唑类衍生物.生物活性测试研究发现,在500μg/m L浓度下,目标化合物对粘虫表现出良好的抑制活性,而且在100μg/m L下,(4-(5-(3-氯苯基)-4-甲基噻唑-2-基)哌啶-1-基)(4-甲基哌嗪-1-基)甲酮(1f)、(5-(3-氯苯基)-4-甲基噻唑-2-基)哌啶-1-基)(4-硝基-1H-吡唑-3-基)甲酮(1g)对粘虫的抑制率均达80%以上,另外在20μg/m L下(5-(3-氯苯基)-4-甲基噻唑-2-基)哌啶-1-基)(4-硝基-1H-吡唑-3-基)甲酮(1g)仍具有50%的杀虫活性.     

新型氨基喹唑啉化合物的合成及其抗肿瘤活性

以2-氰基-4-硝基苯胺为原料,设计并合成了6个新型的氨基喹唑啉类化合物(5a~5c和6a~6c),其结构经1H NMR,13C NMR和ESI-MS表征。初步的抗肿瘤活性测定结果表明,6-(4-甲酸甲酯苯甲酰胺基)-4-(4-甲基-3-三氟甲基苯胺基)喹唑啉(5b)对人乳腺癌细胞MDA-MB-231和人宫颈癌细胞HELA的抑制活性较好,其IC50分别为4.50μM和3.3μM,优于阳性对照药Gefitinib。     

新型吡唑酰腙类化合物的合成及其生物活性

以取代肼和取代乙酰乙酸乙酯为起始原料,依次经闭环、氯酰化、氧化、酯化及取代反应制得1,3-取代-5-氯-4-吡唑甲酰肼(7a,7d,7g和7j);7分别与取代呋喃或噻吩甲醛经加成反应合成了12个新型的吡唑酰腙类化合物(9a~9l),其结构经1H NMR,13C NMR,IR和元素分析表征。初步的生物活性测试结果表明:在500μg·m L-1浓度下,部分化合物对烟草花叶病毒(TMV)具有一定的抑制活性,其中1-苯基-3-三氟甲基-5-氯-4-(2-噻吩)-腙基羰基吡唑(9k)的治疗活性、保护活性和钝化活性分别为63.6%,85.7%和93.1%,与对照药宁南霉素(65.9%,86.4%和97.8%)相当;在50μg·m L-1浓度下,部分化合物表现出一定的抑菌活性,其中1,3-二甲基-5-氯-4-(2-噻吩)-腙基羰基吡唑(9b)与1-甲基3-三氟甲基-5-氯-4-(2-噻吩)-腙基羰基吡唑(9e)对小麦赤霉病菌(Gibberella zeae)的抑制率分别为42.5%和46.8%。     

含苯并香豆素的喹唑啉-4-酮衍生物的合成及其抗肿瘤、抗菌活性

利用Heck偶联反应制备了3,4-苯并香豆素醛,继而与邻氨基苯甲酰胺反应,设计合成了连有苯并香豆素并含氨基侧链的喹唑啉-4-酮衍生物3a~3e和4a,并评价了化合物的抗肿瘤细胞增殖活性及抑菌活性.化合物3e和4a具有中等的抗宫颈癌和乳腺癌细胞增殖活性,IC_(50)值分别为22.63和23.35μmol/L.部分化合物(50μg/m L)对大肠杆菌具有显著的抑制活性,抑菌率在89%以上.2-苯基-4-[2-(哌啶-1-基)乙氧基]喹唑啉(1b)对尖孢镰刀菌和立枯丝核菌以及3d对大丽轮枝菌真菌的抑制率均为100%.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

A carbanion induced synthesis of highly congested pyrazole and imidazole containing heterocycles

An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.     

Selective synthesis of 4,5-dihydroimidazo- and imidazo[1,5-a]quinoxalines via modified Pictet–Spengler reaction

An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction.     

Understanding the Diels-Alder reactivity of 1,2-azaborine analogues

The Diels-Alder reactivity of 1,2-heteroborines (H₄C₄B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.     

Synthesis of N-substituted carbazolones from α-iodo enaminones via Pd(0)-catalyzed intramolecular coupling under microwave irradiation

A variety of N-aryl and N-alkyl carbazolones were conveniently achieved in good to high yields via Pd₂(dba)₃-mediated intramolecular coupling of N-substituted α-iodo enaminones under microwave irradiation. The Pd(0)-catalyzed cyclization was found to proceed favorably with the more electron-deficient phenyl ring during the reactions involving unsymmetrical N,N-diaryl α-iodo enaminones. This unique property enables the construction of carbazolone skeleton containing nitro substituted benzenoid ring.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.