Distribution and geochemical significance of dibenzofurans,phenyldibenzofurans and benzo[b]naphthofurans in source rock extracts from Niger Delta basin,Nigeria

The distribution and geochemical significance of dibenzofurans,phenyldibenzofurans and benzo[b]naptho-furans in source rocks from Niger Delta basin,Nigeria,were investigated by Rock-Eval pyrolysis and gas chro-matography--mass spectrometry(GC--MS).The data obtained from the source rocks evaluation showed that the rock samples contained type 1/III kerogen capable of generating oil and gas and were within immature to early mature stage.The relative abundance of the Cor,C1-and C2-dibenzofurans range from 1.75%to 29.82%,27.60%to 40.52%and 29.66%to 6889%,respectively.The diben-zofurans were dominated by C-dibenzofurans.Among the C1-dibenzofurans,2-+3-methyldibenzofuran was the most abundant in the rock samples while 1-methy ldibenzofuran appeared to be the least.The relative abundance of benzo[b]naphtho[1,2-d]furan(1,2]BNF),benzo[b]naph-tha[2,1-d]furan(2.1]BNF)and benzo[b]naphtha[2,3-d]fu-ran([2.3]BNF)in the rock extracts range from 12.01%to 52.58%,32.61%to 75.219%and 10.27%to 52.43%.The wide range of values recorded for the three isomers of benzo[b lnapthofurans in the samples suggest source rocks formed from mixed organic matter.Among the pheny ldibenzofuran isomers,4-pheny ldibenzofuran was the most abundant while 1-phenyldibenzofuran was the least.Phenyldibenzofuran ratio-1(PhFR-1)and pheny ldibenzofuran ratio-2(PhFR-2)values range from 0.13 to 1.20 and 0.11 to 2.11,respectively.The resuls showed that the relative abundance of PhFR-1 and PhFR-2 increase gradually with increasing burial depth and maturity(VRo≤0.77%,MPI-1≤0.62.Tmax s 443℃),and have a good correlations with calculated vitrinite reflectance.MPI-I and maximum Temperature(Tmax)-This range of values suggested immature to early mature source rocks.The source rocks were found to have shale and coul lithologics and deposited in a lacustrine/fuvial deltaic settings within immature to early mature stages based on the distribution of dibenzofurans,pheny ldiben-zofurans and benzo[b]naphthofurans in the source rocks.This study showed that dibenzof urans,phenyldibenzofu-rans and benzo[b]naphthofurans were ffcive in deter-mining the origin,depositional environment and thermal maturity of source rocks in Niger Delta basin,Nigeria.

Synthesis of 2-aryl-5-alkyl-7-methoxylbenzo[b]furan derivatives

A series of 2-aryl-5-alkyl-7-methoxylbenzo[b]furan derivatives have been synthesized by utilizing the coupling of methyl 3- methoxy-4hydroxy-5-bromocinnamate with cuprous phenylacetylide as the key step. The structures of the new compounds were confirmed by 1H NMR, IR and MS. The structure of compound 14 was further confirmed by single crystal X-ray. Compound 17 showed cytotoxic activity against human lung carcinoma A549.

Synthesis and Crystal Structure of Methyl(7,7-Dimethyl-2-amino-4-(4-chlorophenyl)-5-oxo-5,6,7,8-tetrahydro-4H-benzo-[b]-pyran-3-yl)Carboxylate

The title compound methyl (7,7-dimethyl-2-amino-4-(4-chlorophenyl)-5-oxo- 5,6,7,8-tetrahydro-4H-benzo-[b]-pyran-3-yl) carboxylate (C19H20ClNO4, Mr = 361.81) was synthesized and crystallized. The crystal belongs to triclinic, space group P ī with a = 8.519(2), b = 10.346(2), c = 11.481(3) ?, ( = 108.16(1), ( = 107.78(2), ( = 91.83(2)(, Z = 2, V = 906.5(3) ?3, Dc = 1.326 g/cm3, ((MoK() = 0.234 mm-1, F(000) = 380, R = 0.0467 and wR = 0.1270 for 3142 observed reflections (I ( 2((I)). X-ray analysis reveals that the C(7), C(8), C(9), O(1), C(10) and C(11) atoms form a six-membered ring which adopts a boat conformation. In the ring, the distances of C(8)-C(9) and C(10)-C(11) are 1.332(3) and 1.357(3) (A), respectively, which indicates that they are C=C double bonds. Another six-membered ring (C(8)-C(9)-C(15)-C(14)-C(13)-C(12)) adopts the half-chair conformation. In addition, there are intermolecular hydrogen bonds in the crystal structure.

A new phenanthro [2,3-b] furan from Pleione bulbocodioides

A novel phenanthro [2,3-b] furan 1, named (3-hydroxy-9-(4′-hydroxy-3′-methoxyphenyl)-11-methoxy-5,6,9,10-tetrahydrophenanthro [2,3-b] furan-10-yl) methyl acetate, and two known phenolic compounds were isolated from the tubers of Pleione bulbocodioides (Franch.) Rolfe. Their structures were elucidated by spectroscopic methods.

Immunotoxicity Effect of Benzo[α]Pyrene on Scallop Chlamys farreri

The toxic effects of benzo[α]pyrene (B[α]P) at different concentrations (0.1, 0.5, 1, 2.5 and 7.5 μgL-1) on scallop (Chlamys farreri) immune system were studied. The results showed that B[α]P had significant toxic effects on the haemocyte counts, neutral red uptake, phagocytosis, bacteriolytic and antibacterial activity (P<0.05), while the seawater control and acetone control had no significant differences. The haemocyte counts, neutral red uptake, phagocytosis and bacteriolytic activity in all B[α]P treatment groups as well as antibacterial activity in groups of 0.5, 1, 2.5 and 7.5 μgL-1 B[α]P decreased significantly (P<0.05). Some of these indices tended to be stable on the sixth day and others on the ninth day, and the indices showed clear time-and concentra- tion-response to B[α]P. Bacteriolytic activity in 0.1μgL-1 B[α]P treatment group and antibacterial activity in 0.1 μgL-1 and 0.5 μgL-1 B[α]P treatment groups increased at the beginning of exposure and reached their peaks on day 1 and day 6, respectively. Following that, both activities decreased gradually and became stable after day 9. When all the indices reached stability, they were significantly lower than those in control group (P<0.05), except for antibacterial activity in 0.1 μgL-1 B[α]P treatment group (P>0.05). Thus, B[α]P has evident toxic effects on scallop immune system, which supports the view that a relationship exists between pollution and immunomodulation in aquatic organisms.

Michael Addition Reaction without Catalyst: The Synthesis of 2-Amino-5, 6, 7, 8-tetrahydro-5-oxo-4-aryl-7, 7-dimethyl- 4H-benzo-[b]-pyran Derivatives

A series of tetrahydrobenzo-[b]-pyran derivative was synthesized by the reaction of arylmethylene malononitrile or arylmethylene cyanoacetate with dimedone in ethylene glycol at 80C without catalyst. The structures of the two products were characterized by X-ray diffraction.

再生水受纳河流自然入渗过程中B(a)P对浅层地下水的影响预测

在调查和监测再生水受纳河流凉水河中苯并芘[B(a)P]浓度的基础上,利用Hydrus-1D耦合GMS模型研究B(a)P的时空分布和迁移演变,预测再生水受纳河流对地下水水质的影响。结果表明:B(a)P在包气带的垂直入渗率为0.102 m^(-1),仅为水运移的0.73%。由于吸附和生物降解作用,B(a)P穿透16 m深的包气带时间约为63年,其中吸附和生物降解的贡献率分别为78.4%和19.3%。当B(a)P与地下水相交,受地下水流的推动,B(a)P的迁移以地下水流方向迁移为主。B(a)P在地下水中沿地下水流方向的迁移速率为6.65 m/a,分别为垂直地下水流方向和垂向迁移速率的2.42倍和16.22倍。时空分布表明,地下水中B(a)P浓度随与河流距离的增加而降低,其在平行地下水流方向、垂直地下水流方向和垂向的衰减率常数分别为1.19×10^(-4)、3.05×10^(-4)和3.67×10^(-3)m^(-1),与迁移率呈负相关。然而,地下水中B(a)P浓度随入渗时间的延长而增加,积累率为7.3×10-2d^(-1)。B(a)P的迁移和积累对以地下水为饮用水的沿岸居民造成潜在的危害,导致地下水安全利用范围在20年内将从平行地下水流方向、垂直地下水流方向和垂向的438、276和19.8 m分别缩减至568、324和27.7 m。

2-苯基苯并[b]呋喃类化合物的Pin1抑制活性研究

本文选取了8个2-苯基苯并[b]呋喃类化合物,以糜蛋白偶联方法检测化合物对Pin1的抑制能力,在50 μmol/L浓度下8个化合物对Pin1酶均有一定的抑制作用,其中化合物b6、b7的抑制作用显著强于阳性对照胡桃醌,IC50值分别达0.658 μmol/L和0.800 μmol/L。以MTT法检测化合物b6、b7对肝癌细胞SK-Hep-1与SNU-423生长抑制活性,化合物b6的IC50值分别为70.40 μmol/L、90.35 μmol/L,化合物b7的IC50值分别为79.83 μmol/L、57.48 μmol/L。本研究获得一些具有较好Pin1抑制活性的2-苯基苯并[b]呋喃类化合物,可为抗肿瘤先导药物的研究提供参考。

Synthetic Studies of Naphtho[2,3-b]furan Moiety Present in Diverse Bioactive Natural Products

The preparation of several functionalized furan derivatives and attempts to transform them into a derivative containing 6H-furo[3,4-b]furanone skeleton towards the construction of naphtho[2,3-b] furan are described. Attempted Pummerer reaction of a furan sulfoxide derivative produced four interesting furan derivatives. Base promoted annulation between methyl 2-(phenylsulfinylmethyl)-3-furoate and 2-cyclohexenone proceeded to give dihydro naphtho[2,3-b]furanone derivative in a regiospecific manner.

Synthesis and Crystal Structure of Ethyl 2-(6-(1,3-Dioxo-4,5,6,7-tetrahydro-1H-isoindol-2(3H)-yl)-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) Butanoate

The title compound ethyl 2-（6-（1,3-dioxo-4,5,6,7-tetrahydro-lH-isoindol-2（3H）- yl）-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4（3H）-yl） butanoate 3 was synthesized by the reaction of ethyl 2-（6-amino-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4（3H）-yl） butanoate with 4,5,6,7- tetraydrophthalic anhydride, and its structure was determined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P2 1/n with a = 9.3469（2）, b = 16.7715（5）, c = 13.7153（4） A, β= 104.9680（10）°, μ = 0.107 mm^-1, Mr = 430.42, V= 2077.08（10） ,A3, Z= 4, Dc = 1.376 g/cm3, F（000） = 904, T= 296（2） K, R = 0.0508 and wR = 0.1478.

2-取代芳基苯并[b]呋喃类化合物的合成

以4-取代苯乙炔化亚铜与3-甲氧基-4-羟基-5-溴肉桂酸甲酯为原料进行缩合反应得到2-取代芳基并[b]呋喃,并将其衍生化,得到14个2-芳基-5-烷基-7-甲氧基苯并[b]呋喃化合物,并确证了其结构.

2-薁基取代苯并[b]呋喃类化合物的合成

以溴代丁二酰亚胺为溴化试剂,对1-氰基-2-甲基薁进行了溴代反应研究,将溴甲基化产物与水杨醛类衍生物在通常的加热反应及微波辐射条件下进行缩合,以较高的收率得到2-薁基取代苯并[b]呋喃,其结构经1HNMR,IR及元素分析等得以证实.

B[a]P累积污染对土壤呼吸强度的影响

Benzo(a)pyrene(B[a]P)是具有"三致"效应的有机污染物,正在以叠加的方式在土壤中逐步累积,对土壤环境质量造成严重威胁。采用叠加实验的方法模拟B[a]P在土壤中的累积过程,研究B[a]P累积污染后的有效性特征及其对土壤呼吸强度的影响。结果表明:在叠加和一次污染方式下,土壤B[a]P可提取含量和有效含量随培养时间的延长呈现初始(1～28 d)下降速率较快,而后(28～56d)逐渐减缓的趋势。在叠加污染条件下,土壤B[a]P可提取量比一次污染条件下降低了34.50%～57.29%,土壤B[a]P有效含量则比一次污染低19.00%～43.80%。土壤呼吸强度随B[a]P培养时间的延长呈现出先减弱,而后逐渐恢复的规律。在两种污染方式下,土壤呼吸强度在前7 d比实验开始时(1 d)减弱了14.38%～35.80%,在8～56 d逐渐恢复并稳定在11.51～15.69 mg·kg-1·h-1之间。土壤呼吸强度随土壤B[a]P有效性的变化而改变,两者呈正相关。研究结果为土壤B[a]P叠加累积污染的生态毒性研究提供科学依据。

翡翠贻贝内脏团抗氧化酶活性及脂质过氧化物含量对苯并(b)荧蒽胁迫的生物响应研究

为了研究苯并(b)荧蒽这一典型的多环芳烃化合物对水生生物的毒性效应,测定了不同浓度(2.0、10.0和50.0μg.L-1)苯并(b)荧蒽胁迫15 d和清水释放10 d后翡翠贻贝(Perna viridis)内脏团组织中抗氧化酶(CAT、SOD和GPx)活性和MDA含量的变化。结果表明,2.0μg.L-1浓度组中CAT活性呈现出诱导-抑制的规律,在第4天达到峰值,诱导率为81.9%;10.0和50.0μg.L-1浓度组中SOD活性在整个胁迫阶段呈现抑制-诱导-抑制的趋势,第2天时抑制率分别为31.9%和49.8%,第8天时诱导率分别为24.9%和62.3%;10.0和50.0μg.L-1浓度组中GPx活性在整个胁迫阶段呈现抑制-诱导的变化规律,第8天抑制率分别为30.6%和40.6%,15 d时诱导率分别为20.6%和21.3%。随着清水释放实验的进行,2.0和10.0μg.L-1浓度组的翡翠贻贝内脏团抗氧化酶活性逐渐恢复,氧化损伤逐渐降低,但50.0μg.L-1浓度组中翡翠贻贝的SOD和GPx活性10 d后仍显著低于对照组水平。本研究中,翡翠贻贝内脏团抗氧化酶活性的变化,可以反映苯并(b)荧蒽在一定浓度与时间范围内对机体的胁迫程度;而MDA含量与苯并(b)荧蒽存在显著的时间-效应和浓度-效应关系,表明苯并(b)荧蒽能通过氧化损伤途径对机体产生毒性作用。

菲和苯并(b)荧蒽曝露对翡翠贻贝外套膜的氧化胁迫及损伤

实验室条件下研究了不同质量浓度(2.0μg.L-1、10.0μg.L-1和50.0μg.L-1)的菲(PHE)和苯并(b)荧蒽(BbF)胁迫15 d和清洁海水恢复7 d中翡翠贻贝(Perna viridis)外套膜组织中超氧化物歧化酶(SOD)活力和丙二醛(MDA)质量摩尔浓度的变化。结果表明,PHE胁迫下翡翠贻贝外套膜SOD活力呈先升高后降低的变化规律;BbF胁迫下的翡翠贻贝外套膜SOD活力在胁迫第15天时被显著诱导(P<0.05)。从b(MDA)的变化来看,PHE和BbF均可导致翡翠贻贝外套膜明显的氧化损伤,之后在清洁海水的净化过程中,这种损伤逐渐降低并恢复至正常水平。鉴于2种PAHs胁迫下翡翠贻贝外套膜SOD活力和b(MDA)均发生明显变化并表现出一定的差异性,翡翠贻贝体内的生化指标适合指示PAHs对海洋环境的污染。

土壤B[a]P多次叠加污染对蚯蚓体腔细胞的毒性效应

苯并[a]芘（benzo[a]pyrene,B[a]P）是多环芳烃类有机污染物,在土壤中逐步累积,对土壤环境造成潜在的威胁。一次污染条件下,B[a]P进入土壤的过程与低剂量逐步累积的过程有一定差异,在一定程度上会高估B[a]P的环境风险。本试验采用多次叠加污染的方法,模拟B[a]P在土壤中逐步累积的过程,研究土壤B[a]P叠加污染的有效性特征及其在蚯蚓（Eisenia foetida）体内的富集规律,分析蚯蚓体腔细胞的毒性效应。结果表明：随着B[a]P在土壤中培养时间的增加,土壤B[a]P有效含量、蚯蚓体内B[a]P富集量和蚯蚓体腔细胞MDA含量均呈前期（1～28 d）下降速率较快,后期（29～56 d）下降速率逐渐减缓的趋势,且蚯蚓体内B[a]P富集量与土壤B[a]P有效含量（Tenax-TA提取量）之间呈极显著正相关（P〈0.01）,相关系数（R2）为0.893 2。叠加污染条件下,0～20 cm和20～40 cm土壤中B[a]P平均有效含量比一次污染低23.38%（P〈0.05,14和28 d的20～40 cm叠加污染土壤除外）;在1、7、14、28和56 d所取土样培养的蚯蚓,其体内B[a]P富集量是一次污染的22.42%～77.42%,蚯蚓体腔细胞MDA含量在14 d时分别比一次污染低13.76%和41.38%,这表明土壤B[a]P多次叠加污染对蚯蚓体腔细胞的毒性效应低于一次污染,叠加污染更能客观反映污染物的真实毒性效应。

分子内Povarov反应合成香豆素并[4,3-b]喹啉类化合物

在p-TsOH作用下,以4-(1-萘氨基)或4-(2-萘胺基)香豆素和芳香醛为基础原料,通过分子内的Povarov反应,高选择性地合成了一系列苯并[h]香豆素并[4,3-b]喹啉和苯并[f]香豆素并[4,3-b]二氢喹啉类化合物。该反应操作简单、条件温和、收率良好。产物结构经IR、NMR及元素分析数据得以证实。

水介质中2-氨基-4-芳基-7,7-二甲基-5-氧代-4H-5,6,7,8-四氢苯并[b]吡喃-3-羧酸酯的有效合成

水介质中在三乙基苄基氯化铵(TEBA)存在下,芳亚甲基氰乙酸酯与5,5-二甲基-1,3-环己二酮反应为2-氨基-4-芳基-7,7-二甲基-5-氧代-4H-5,6,7,8-四氢苯并[b]吡喃-3-羧酸酯提供了一种快速、方便、高效和洁净的合成方法.产物的结构通过红外光谱、核磁共振氢谱、元素分析和单晶X射线衍射确定.