18 research outputs found
1-Benzylsulfanyl-2-[(2-chlorophenyl)diazenyl]benzene
The title compound, C19H15ClN2S, a divalent organosulfur compound belonging to the class of ortho-mercaptoazo compounds, is non-ionic in nature. The azo group in the molecule is moved away from the S atom to attain the stable trans-azo configuration. Here the S atom is not electron deficient, so no intramolecular N⋯S interaction exists. Due to steric reasons, the molecule is non-planar: the chlorophenyl and benzyl rings are oriented at dihedral angles of 3.21 (8) and 78.18 (5)°, respectively, with respect to the thiophenyl ring. There are no hydrogen bonds and the crystal structure is stabilized by van der Waals interactions
Climate Resilient Agriculture Experiences from NICRA Implementation in North Bank Plains Zone of Assam
Not AvailableClimate change impacts on agriculture are being witnessed all over the world, but
countries like India are more vulnerable in view of the huge population dependent on
agriculture, excessive pressure on natural resources and poor coping mechanisms. The
warming trend in India over the past 100 years has indicated an increase of 0.60°C. The
projected impacts are likely to further aggravate field fluctuations of many crops thus
impacting food security. There are already evidences of negative impacts on yield of wheat
and paddy in parts of India due to increased temperature, water stress and reduction in
number of rainy days. Increased abnormalities in amount and distribution of rainfall has also
been observed in North Bank Plains Zone (NBPZ) of Assam along with increase in numbers
of wet spell driven flash floods and seasonal droughts in recent years.
Planned adaption is essential to increase the resilience of agricultural production to
climate change. Several improved agricultural practices evolved over time for diverse agroecological
regions in India have potential to enhance climate change adaptation, if deployed
prudently. Management practices that increase agricultural production under adverse climatic
conditions also tend to support climate change adaptation because they increase resilience
and reduce yield variability under variable climate and extreme events.
Keeping this in view, National Innovations on Climate Resilient Agriculture was
implemented under All India Coordinated Research Project for Dryland Agriculture,
Biswanath Chariali centre on 2011in two selected villages of North Lakhimpur, Chamua and
Ganakdoloni. The main aim of the project is to enhance resilience of Indian agriculture to
climate change and climate variability through strategic research and technology
demonstration.
In this bulletin the authors have penned down the experiences gained from
implementation of NICRA in NBPZ of Assam. It is hoped that the bulletin will be able to
serve the purposes towards achieving its objectives and act as a benchmark study for the
entire area. It is expected that the information contained in this bulletin will be exploited by
the scientist of different disciplines and extension officials for making rational
recommendation.
The authors will remain ever grateful to Project Coordinator, (AICRPDA), CRIDA,
Hyderabad and Director of Research (Agri), AAU for their guidance, encouragement and
sincere support. The authors extend thankfulness to the fellow Scientists, Research
Associates and other technical staff for their cooperation and help. The authors express their
thankfulness to Sharada Offset, Biswanath Chariali for printing the report.Not Availabl
Multienzyme Immobilized Polymeric Membrane Reactor for the Transformation of a Lignin Model Compound
We have developed an integrated, multienzyme functionalized membrane reactor for bioconversion of a lignin model compound involving enzymatic catalysis. The membrane bioreactors were fabricated through the layer-by-layer assembly approach to immobilize three different enzymes (glucose oxidase, peroxidase and laccase) into pH-responsive membranes. This novel membrane reactor couples the in situ generation of hydrogen peroxide (by glucose oxidase) to oxidative conversion of a lignin model compound, guaiacylglycerol-β-guaiacyl ether (GGE). Preliminary investigation of the efficacy of these functional membranes towards GGE degradation is demonstrated under convective flow mode. Over 90% of the initial feed could be degraded with the multienzyme immobilized membranes at a residence time of approximately 22 s. GGE conversion product analysis revealed the formation of oligomeric oxidation products upon reaction with peroxidase, which may be a potential hazard to membrane bioreactors. These oxidation products could further be degraded by laccase enzymes in the multienzymatic membranes, explaining the potential of multi enzyme membrane reactors. The multienzyme incorporated membrane reactors were active for more than 30 days of storage time at 4 °C. During this time span, repetitive use of the membrane reactor was demonstrated involving 5–6 h of operation time for each cycle. The membrane reactor displayed encouraging performance, losing only 12% of its initial activity after multiple cycles of operation
Design, Synthesis, and Preliminary Evaluation of a Potential Synthetic Opioid Rescue Agent
BACKGROUND: One of the most prominent opioid analgesics in the United States is the high potency agonist fentanyl. It is used in the treatment of acute and chronic pain and as an anesthetic adjuvant. When used inappropriately, however, ingestion of just a few milligrams of fentanyl or other synthetic opioid can cause opioid-induced respiratory depression (OIRD), often leading to death. Currently, the treatment of choice for OIRD is the opioid receptor antagonist naloxone. Recent reports, however, suggest that higher doses or repeated dosing of naloxone (due to recurrence of respiratory depression) may be required to reverse fully fentanyl-induced respiratory depression, rendering this treatment inadequate. To combat this synthetic opioid overdose crisis, this research aims at identifying a novel opioid reversal agent with enhanced efficacy towards fentanyl and other synthetic opioids.
METHODS: A series of naltrexone analogues were characterized for their ability to antagonize the effects of fentanyl in vitro utilizing a modified forskolin-induced cAMP accumulation assay. Lead analogue 29 was chosen to undergo further PK studies, followed by in vivo pharmacological analysis to determine its ability to antagonize opioid-induced antinociception in the hot plate assay.
RESULTS: A series of potent MOR antagonists were identified, including the highly potent analogue 29 (IC50 = 2.06 nM). Follow-up PK studies revealed 29 to possess near 100% bioavailability following IP administration. Brain concentrations of 29 surpassed plasma concentrations, with an apparent terminal half-life of ~ 80 min in mice. In the hot plate assay, 29 dose-dependently (0.01–0.1 mg/kg; IP) and fully antagonized the antinociception induced by oxycodone (5.6 mg/kg; IP). Furthermore, the dose of 29 that is fully effective in preventing oxycodone-induced antinociception (0.1 mg/kg) was ineffective against locomotor deficits caused by the KOR agonist U50,488.
CONCLUSIONS: Methods have been developed that have utility to identify enhanced rescue agents for the treatment of OIRD. Analogue 29, possessing potent MOR antagonist activity in vitro and in vivo, provides a promising lead in our search for an enhanced synthetic opioid rescue agent
Adaptation Strategies for Climate Variability in the High Rainfall Zone of India, Assam
The NICRA project is being implemented in two villages viz., Chamua (since 2010–2011) and Ganakdalani (since 2012–2013 till 2016–2017), which are situated in the west of Lakhimpur district of North Bank Plains Zone of Assam. Chamua village is situated in Kherajkhat Mauza (Taluka), which is 45 km away from North Lakhimpur, the headquarter of district Lakhimpur. On the other hand, Ganakdoloni is situated at Dhalpur Mauza, situated 60 km away from North Lakhimpur and 15 km away from the local township Narayanpur. During 2017–2018 four villages viz., Jakaipelua, Borbali, Borkhet, and Nogaya were adopted under the project. Analysis of long-term rainfall data confirmed the significant decreasing trend of annual as well as monsoonal rainfall in both the Brahmaputra and Barak basins of Assam, India. Variability of rainfall has been increasing in terms of the increased frequency of high-intensity rains and the reduced number of rainy days, leading to localized flash floods and the occurrence of multiple dry spells. Mean season-wise rainfall 2011–2021 indicates long dry periods during the winter season, leading to prolonged dry spells affecting crop growth. About 69% of total rainfall (average annual rainfall of Assam is 2000 mm) is received during the monsoon season, resulting in flash floods leading to crop damage. Out of 12 years of investigation, 10 years are deficit years, resulting in crop stress both during the monsoon and post-monsoon period. Preparation and implementation of real-time crop contingencies are important in responding to weather aberrations in different strategies like preparedness, real-time response, etc. Identification of various adaptation strategies, including climate-resilient crops and cultivars, rainwater harvesting and recycling, efficient energy management through farm mechanization, dissemination of weather information, and weather-based agro-advisories to farmers in a real-time basis, is important adaptation technologies for building climate-resilient agriculture. The study showed that adaption of climate-resilient crop and cropping system and use of harvested rainwater resulted in a 12 to 30% increase in yield observed by the cultivation of high-yielding rice varieties (HYVs) (Ranjit, Gitesh, Mahsuri, etc.) when sown in time (before 15th June) over late sowing conditions (after 20th June). In the case of early season drought, replacement of long duration traditional varieties with short duration HYV and life-saving irrigation using harvested rainwater increased yield by about 59% (short duration var. Dishang) over non-irrigated fields. In case of mid-season and terminal drought, application of an additional dose of 22 kg ha−1 MOP at maximum tillering to grain growth period an increase in yield of about 33% (Ranjit), 32% (Gitesh), 64% (Shraboni), and 57.5% (Mulagabharu) has been observed over farmers’ practice. In highly flood-affected areas under lowland situations replacement of submergence tolerant varieties (Jalashree and Jalkuwari) with traditional deepwater rice varieties resulted in reduced crop loss due to the genetic trait of the deepwater rice, which can withstand water logging for a long period. With an increase in the level of mechanization through the use of machinery available in the custom hiring center the human and animal hour requirement for paddy cultivation was reduced from 795 to 350 hrha−1 and 353 to 23 hrha−1, respectively. Alternate land use in terms of low-cost poly house, vermicompost production, and mushroom cultivation also resulted in nutritional security and generation of higher income for the farmer
Disulfides, Imines, and Metal Coordination within a Single System: Interplay between Three Dynamic Equilibria
We report a system in which three distinct dynamic linkages, disulfide (S-S), imine (C=N), and coordinative (N→metal) bonds were shown to be capable of simultaneous reversible exchange. The “disulfide layer” of the system under study consists of two homo-disulfides, bis(4-aminophenyl) disulfide 1 and bis(4-methoxyphenyl) disulfide 2 that equilibrate in the presence of catalytic amount of triethylamine to favor the formation of a hetero-disulfide product, 4-aminophenyl-4’-methoxyphenyl disulfide 3. The addition of 2-formylpyridine and a metal salt strongly perturbed this 1+2⇄3 equilibrium through the formation of metal complexes incorporating disulfide 1 as a subcomponent. CuI perturbed the equilibrium by a factor of 3.3, and FeII by a factor of 179, in both cases in favor of the homo-disulfides. The disulfide equilibrium could be further modified, following metal-complex formation, by coordinative (transmetallation: substitution of FeII for CuI) or covalent (imine exchange: the substitution of one amine residue for another) exchange. Thus, although the three kinds of dynamic linkages were demonstrated to be mutually compatible, changes at one kind of linkage could be used to predictably perturb an equilibrium involving another
Multienzyme Immobilized Polymeric Membrane Reactor for the Transformation of a Lignin Model Compound
We have developed an integrated, multienzyme functionalized membrane reactor for bioconversion of a lignin model compound involving enzymatic catalysis. The membrane bioreactors were fabricated through the layer-by-layer assembly approach to immobilize three different enzymes (glucose oxidase, peroxidase and laccase) into pH-responsive membranes. This novel membrane reactor couples the in situ generation of hydrogen peroxide (by glucose oxidase) to oxidative conversion of a lignin model compound, guaiacylglycerol-β-guaiacyl ether (GGE). Preliminary investigation of the efficacy of these functional membranes towards GGE degradation is demonstrated under convective flow mode. Over 90% of the initial feed could be degraded with the multienzyme immobilized membranes at a residence time of approximately 22 s. GGE conversion product analysis revealed the formation of oligomeric oxidation products upon reaction with peroxidase, which may be a potential hazard to membrane bioreactors. These oxidation products could further be degraded by laccase enzymes in the multienzymatic membranes, explaining the potential of multi enzyme membrane reactors. The multienzyme incorporated membrane reactors were active for more than 30 days of storage time at 4 °C. During this time span, repetitive use of the membrane reactor was demonstrated involving 5–6 h of operation time for each cycle. The membrane reactor displayed encouraging performance, losing only 12% of its initial activity after multiple cycles of operation
Microwave-Promoted Catalyst- and Solvent-Free Aza-Diels–Alder Reaction of Aldimines with 6-[2-(Dimethylamino)vinyl]-1,3-dimethyluracil
A microwave-promoted aza-Diels–Alder reaction
between 6-[2-(dimethylamino)vinyl]-1,3-dimethyluracil
and aldimines has been developed for the construction of dihydropyrido[4,3-<i>d</i>]pyrimidines. Urea is effectively employed as an environmentally
benign source of ammonia in the absence of any catalyst or solvent.
The key step in the reaction is in situ generation and trapping of
the reactive aldimine formed from urea and aldehyde by the diene system
of the uracil. The reaction is clean, and excellent yields are obtained
in a matter of a few minutes