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Arthur G. Schultz - One of the best experts on this subject based on the ideXlab platform.
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ammonia promoted fragmentation of 2 alkyl and 2 4 dialkyl 3 iodo 1 oxocyclohexan 2 4 carbolactones
Journal of Organic Chemistry, 2005Co-Authors: Mingshi Dai, Seock-kyu Khim, Xuqing Zhang, Arthur G. SchultzAbstract:2-Alkyl- and 2,4-dialkyl-3-iodo-1-oxocyclohexan-2,4-carbolactones undergo ammonia-promoted fragmentation reactions to provide Butenolides, γ-butyrolactone, and/or β,γ-epoxycyclohexanones. Product distribution is governed by the relative size of the substituents at C-2 and C-4 of the cyclohexanones. Butenolide amide, the major product from the fragmentation, is further converted into their respective piperidinone and pyrrolidine derivatives.
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Novel fragmentation reaction of 2-alkyl- and 2,4-dialkyl-3-iodo-1-oxocyclohexan-2,4-carbolactones.
The Journal of organic chemistry, 2004Co-Authors: Seock-kyu Khim, Mingshi Dai, Xuqing Zhang, Lei Chen, Liping Pettus, Kshitij Chhabilbhai Thakkar, Arthur G. SchultzAbstract:2-Alkyl- and 2,4-dialkyl-3-iodo-1-oxocyclohexan-2,4-carbolactones undergo lithium hydroxide- and lithium alkoxide-induced fragmentation reactions to provide Butenolides, gamma-hydroxycyclohexenones, and/or gamma-butyrolactones. In general, product distribution is governed by two factors: (1) the nature of nucleophiles and (2) the steric bulkiness of the substituents at C-2 and C-4 of the cyclohexanones. Lithium hydroxide-induced fragmentation provides Butenolides and gamma-hydroxycyclohexenones. In contrast, lithium alkoxide-promoted fragmentation results in predominantly 5-substituted gamma-butyrolactones along with a small amount of Butenolides in limited cases. Fragmentation products induced by lithium hydroxide are largely influenced by the steric bulkiness of the substituents at C-2 and C-4 of the cyclohexanone ring. The bulky substituents render the exclusive formation of Butenolides.
Peiyuan Qian - One of the best experts on this subject based on the ideXlab platform.
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Synthetic Analogue of Butenolide as an Antifouling Agent
'MDPI AG', 2021Co-Authors: Ho Yin Chiang, Jinping Cheng, Xuan Liu, Peiyuan QianAbstract:Butenolide derivatives have the potential to be effective and environmentally friendly antifouling agents. In the present study, a Butenolide derivative was structurally modified into Boc-Butenolide to increase its melting point and remove its foul smell. The structurally modified Boc-Butenolide demonstrated similar antifouling capabilities to Butenolide in larval settlement bioassays but with significantly lower toxicity at high concentrations. Release-rate measurements demonstrated that the antifouling compound Boc-Butenolide could be released from polycaprolactone-polyurethane (PCL-PU)-based coatings to inhibit the attachment of foulers. The coating matrix was easily degraded in the marine environment. The performance of the Boc-Butenolide antifouling coatings was further examined through a marine field test. The coverage of biofouler on the Boc-Butenolide coatings was low after 2 months, indicating the antifouling potential of Boc-Butenolide
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optimization of antifouling coatings incorporating Butenolide a potent antifouling agent via field and laboratory tests
Progress in Organic Coatings, 2017Co-Authors: Lianguo Chen, Peiyuan QianAbstract:Rosin-based antifouling paint with the incorporation of Butenolide, a promising antifoulant, possesses the potential to deter the settlement of marine organisms on submerged surfaces. With the purpose to extend the antifouling duration, this research investigated the respective contribution of paint ingredients, including Butenolide concentrations (5%, 10% and 15%), pigment choices (TiO2, Fe2O3, Cu2O and ZnO) and binder compositions (acrylic copolymer to rosin at 1: 2.5, 1.5: 2 and 2.5: 1), to the field antifouling performance of Butenolide. A raft trial was carried out at Yung Shue 0, Hong Kong after the application of antifouling paints on PVC panels. Biofouling dynamics on panel surfaces, such as coverage percentage and biomass accumulation, were monitored until submersion for 6 months to allow for the assessment of antifouling efficiency. Field results showed that Butenolide incorporation generally inhibited the settlement of fouling species on the coated panels as demonstrated by the decreased surface coverage and biomass weight. Coatings with 1: 2.5 paints containing 10% Butenolide exhibited the best antifouling performance with only 34% of the surface covered by fouling organisms, which mainly consisted of algae and slime. The smallest biomass increase of the fouling community was also observed for 1: 2.5 coatings. An increased proportion of rosin in binder compositions yielded better antifouling performance following the order of 1: 2.5 > 1.5: 2 > 2.5: 1. Laboratory experiments were also conducted to examine the behavior of paint coatings in stirring artificial seawater. Butenolide addition decreased the film hardness and inhibited water uptake, but resulted in weight loss of paint coatings. Along with the gradual release of Butenolide, the hardness of paint films increased gradually. Overall, a service life of 6 months, while eliminating the use of heavy metals, highlights the effectiveness of Butenolide-incorporated paint formulation, especially 1: 2.5 paint, as an environmentally benign and fouling-resistant candidate for future antifouling application.
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degradation kinetics of a potent antifouling agent Butenolide under various environmental conditions
Chemosphere, 2015Co-Authors: Lianguo Chen, Ying Xu, Wenxiong Wang, Peiyuan QianAbstract:Abstract Here, we investigated the degradation kinetics of Butenolide, a promising antifouling compound, under various environmental conditions. The active ingredient of the commercial antifoulant SeaNine 211, 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (DCOIT), was used as positive control. The results showed that the degradation rate increased with increasing temperature. Half-lives of Butenolide at 4 °C, 25 °C and 40 °C were >64 d, 30.5 d and 3.9 d, respectively. Similar half-lives were recorded for DCOIT: >64 d at 4 °C, 27.9 d at 25 °C and 4.5 d at 40 °C. Exposure to sunlight accelerated the degradation of both Butenolide and DCOIT. The photolysis half-lives of Butenolide and DCOIT were 5.7 d and 6.8 d, respectively, compared with 9.7 d and 14.4 d for the dark control. Biodegradation led to the fastest rate of Butenolide removal from natural seawater, with a half-life of 0.5 d, while no obvious degradation was observed for DCOIT after incubation for 4 d. The biodegradative ability of natural seawater for Butenolide was attributed mainly to marine bacteria. During the degradation of Butenolide and DCOIT, a gradual decrease in antifouling activity was observed, as indicated by the increased settlement percentage of cypris larvae from barnacle Balanus amphitrite . Besides, increased cell growth of marine diatom Skeletonema costatum demonstrated that the toxicity of seawater decreased gradually without generation of more toxic by-products. Overall, rapid degradation of Butenolide in natural seawater supported its claim as a promising candidate for commercial antifouling industry.
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comparative safety of the antifouling compound Butenolide and 4 5 dichloro 2 n octyl 4 isothiazolin 3 one dcoit to the marine medaka oryzias melastigma
Aquatic Toxicology, 2014Co-Authors: Lianguo Chen, Ying Xu, Rui Ye, Doris W T Au, Peiyuan QianAbstract:Abstract This study evaluated the potential adverse effects of Butenolide, a promising antifouling compound, using the marine medaka (Oryzias melastigma), a model fish for marine ecotoxicology. The active ingredient used in the commercial antifoulant SeaNine 211, 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (DCOIT) was employed as the positive control. Adult marine medaka (4-month-old) were exposed to various concentrations of Butenolide or DCOIT for 28 days and then depurated in clean seawater for 14 days (recovery). A suite of sensitive biomarkers, including hepatic oxidative stress, neuronal signal transmission, endocrine disruption, and reproductive function, was used to measure significant biological effects induced by the chemicals. Compared to DCOIT, chronic exposure to Butenolide induced a lower extent of oxidative stress in the liver of male and female medaka. Furthermore, Butenolide-exposed fish could recover faster from oxidative stress than fish exposed to DCOIT. Regarding neurotransmission, DCOIT significantly inhibited acetylcholinesterase (AChE) activity in the brain of both male and female medaka, whereas this was not significant for Butenolide. In addition, plasma estradiol (E2) level was elevated and testosterone (T) level was decreased in male medaka exposed to DCOIT. This greatly imbalanced sex hormones ratio (E2/T) in exposed males, indicating that DCOIT is a potent endocrine disruptive chemical. In contrast, Butenolide induced only moderate effects on sex hormone levels in exposed males, which could be gradually recovered during depuration. Moreover, the endocrine disruptive effect induced by Butenolide did not affect normal development of offspring. In contrast, DCOIT-exposed fish exhibited a decrease of egg production and impaired reproductive success. Overall, the above findings demonstrated that chronic exposure to Butenolide induced transient, reversible biological effect on marine medaka, while DCOIT could impair reproductive success of fish, as evident by clear alterations of the E2/T ratio. The relatively low toxicity of Butenolide on marine biota highlights its promising application in the antifouling industry. The present findings also emphasize gender difference in fish susceptibility to chemical treatment (male > female), which is an important consideration for ecological risk assessment.
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the effect of Butenolide on behavioral and morphological changes in two marine fouling species the barnacle balanus amphitrite and the bryozoan bugula neritina
Biofouling, 2011Co-Authors: Yi-fan Zhang, Xu Ying, Guangchao Wang, Rachid Sougrat, Peiyuan QianAbstract:Butenolide [5-octylfuran-2(5H)-one] is a very promising antifouling compound. Here, the effects of Butenolide on larval behavior and histology are compared in two major fouling organisms, viz. cypris larvae of Balanus amphitrite and swimming larvae of Bugula neritina. Butenolide diminished the positive phototactic behavior of B. amphitrite (EC50=0.82 μg ml(-1)) and B. neritina (EC50=3 μg ml(-1)). Its effect on the attachment of cyprids of B. amphitrite was influenced by temperature, and Butenolide increased attachment of larvae of B. neritina to the bottom of the experimental wells. At concentrations of 4 μg ml(-1) and 10 μg ml(-1), Butenolide decreased attachment of B. amphitrite and B. neritina, respectively, but the effects were reversible within a certain treatment time. Morphologically, Butenolide inhibited the swelling of secretory granules and altered the rough endoplasmic reticulum (RER) in the cement gland of B. amphitrite cyprids. In B. neritina swimming larvae, Butenolide reduced the number of secretory granules in the pyriform-glandular complex.
Mingshi Dai - One of the best experts on this subject based on the ideXlab platform.
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ammonia promoted fragmentation of 2 alkyl and 2 4 dialkyl 3 iodo 1 oxocyclohexan 2 4 carbolactones
Journal of Organic Chemistry, 2005Co-Authors: Mingshi Dai, Seock-kyu Khim, Xuqing Zhang, Arthur G. SchultzAbstract:2-Alkyl- and 2,4-dialkyl-3-iodo-1-oxocyclohexan-2,4-carbolactones undergo ammonia-promoted fragmentation reactions to provide Butenolides, γ-butyrolactone, and/or β,γ-epoxycyclohexanones. Product distribution is governed by the relative size of the substituents at C-2 and C-4 of the cyclohexanones. Butenolide amide, the major product from the fragmentation, is further converted into their respective piperidinone and pyrrolidine derivatives.
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Novel fragmentation reaction of 2-alkyl- and 2,4-dialkyl-3-iodo-1-oxocyclohexan-2,4-carbolactones.
The Journal of organic chemistry, 2004Co-Authors: Seock-kyu Khim, Mingshi Dai, Xuqing Zhang, Lei Chen, Liping Pettus, Kshitij Chhabilbhai Thakkar, Arthur G. SchultzAbstract:2-Alkyl- and 2,4-dialkyl-3-iodo-1-oxocyclohexan-2,4-carbolactones undergo lithium hydroxide- and lithium alkoxide-induced fragmentation reactions to provide Butenolides, gamma-hydroxycyclohexenones, and/or gamma-butyrolactones. In general, product distribution is governed by two factors: (1) the nature of nucleophiles and (2) the steric bulkiness of the substituents at C-2 and C-4 of the cyclohexanones. Lithium hydroxide-induced fragmentation provides Butenolides and gamma-hydroxycyclohexenones. In contrast, lithium alkoxide-promoted fragmentation results in predominantly 5-substituted gamma-butyrolactones along with a small amount of Butenolides in limited cases. Fragmentation products induced by lithium hydroxide are largely influenced by the steric bulkiness of the substituents at C-2 and C-4 of the cyclohexanone ring. The bulky substituents render the exclusive formation of Butenolides.
Seock-kyu Khim - One of the best experts on this subject based on the ideXlab platform.
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ammonia promoted fragmentation of 2 alkyl and 2 4 dialkyl 3 iodo 1 oxocyclohexan 2 4 carbolactones
Journal of Organic Chemistry, 2005Co-Authors: Mingshi Dai, Seock-kyu Khim, Xuqing Zhang, Arthur G. SchultzAbstract:2-Alkyl- and 2,4-dialkyl-3-iodo-1-oxocyclohexan-2,4-carbolactones undergo ammonia-promoted fragmentation reactions to provide Butenolides, γ-butyrolactone, and/or β,γ-epoxycyclohexanones. Product distribution is governed by the relative size of the substituents at C-2 and C-4 of the cyclohexanones. Butenolide amide, the major product from the fragmentation, is further converted into their respective piperidinone and pyrrolidine derivatives.
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Novel fragmentation reaction of 2-alkyl- and 2,4-dialkyl-3-iodo-1-oxocyclohexan-2,4-carbolactones.
The Journal of organic chemistry, 2004Co-Authors: Seock-kyu Khim, Mingshi Dai, Xuqing Zhang, Lei Chen, Liping Pettus, Kshitij Chhabilbhai Thakkar, Arthur G. SchultzAbstract:2-Alkyl- and 2,4-dialkyl-3-iodo-1-oxocyclohexan-2,4-carbolactones undergo lithium hydroxide- and lithium alkoxide-induced fragmentation reactions to provide Butenolides, gamma-hydroxycyclohexenones, and/or gamma-butyrolactones. In general, product distribution is governed by two factors: (1) the nature of nucleophiles and (2) the steric bulkiness of the substituents at C-2 and C-4 of the cyclohexanones. Lithium hydroxide-induced fragmentation provides Butenolides and gamma-hydroxycyclohexenones. In contrast, lithium alkoxide-promoted fragmentation results in predominantly 5-substituted gamma-butyrolactones along with a small amount of Butenolides in limited cases. Fragmentation products induced by lithium hydroxide are largely influenced by the steric bulkiness of the substituents at C-2 and C-4 of the cyclohexanone ring. The bulky substituents render the exclusive formation of Butenolides.
Xuqing Zhang - One of the best experts on this subject based on the ideXlab platform.
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ammonia promoted fragmentation of 2 alkyl and 2 4 dialkyl 3 iodo 1 oxocyclohexan 2 4 carbolactones
Journal of Organic Chemistry, 2005Co-Authors: Mingshi Dai, Seock-kyu Khim, Xuqing Zhang, Arthur G. SchultzAbstract:2-Alkyl- and 2,4-dialkyl-3-iodo-1-oxocyclohexan-2,4-carbolactones undergo ammonia-promoted fragmentation reactions to provide Butenolides, γ-butyrolactone, and/or β,γ-epoxycyclohexanones. Product distribution is governed by the relative size of the substituents at C-2 and C-4 of the cyclohexanones. Butenolide amide, the major product from the fragmentation, is further converted into their respective piperidinone and pyrrolidine derivatives.
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Novel fragmentation reaction of 2-alkyl- and 2,4-dialkyl-3-iodo-1-oxocyclohexan-2,4-carbolactones.
The Journal of organic chemistry, 2004Co-Authors: Seock-kyu Khim, Mingshi Dai, Xuqing Zhang, Lei Chen, Liping Pettus, Kshitij Chhabilbhai Thakkar, Arthur G. SchultzAbstract:2-Alkyl- and 2,4-dialkyl-3-iodo-1-oxocyclohexan-2,4-carbolactones undergo lithium hydroxide- and lithium alkoxide-induced fragmentation reactions to provide Butenolides, gamma-hydroxycyclohexenones, and/or gamma-butyrolactones. In general, product distribution is governed by two factors: (1) the nature of nucleophiles and (2) the steric bulkiness of the substituents at C-2 and C-4 of the cyclohexanones. Lithium hydroxide-induced fragmentation provides Butenolides and gamma-hydroxycyclohexenones. In contrast, lithium alkoxide-promoted fragmentation results in predominantly 5-substituted gamma-butyrolactones along with a small amount of Butenolides in limited cases. Fragmentation products induced by lithium hydroxide are largely influenced by the steric bulkiness of the substituents at C-2 and C-4 of the cyclohexanone ring. The bulky substituents render the exclusive formation of Butenolides.
