Alpha Naphthyl Acetic Acid: Chemistry and Applications


Intro
Alpha naphthyl acetic acid (ANA) serves as a significant compound within the realms of chemistry and agriculture. Its unique chemical properties present intriguing possibilities, particularly in plant growth regulation and recent explorations in pharmacology. Understanding ANAβs role requires diving into its synthesis routes, applications, and the evolving body of research surrounding its environmental impact and future potential.
Research Overview
Summary of Key Findings
The examination of alpha naphthyl acetic acid has yielded several important insights, including its ability to regulate plant growth by enhancing cell division and elongation. Research has also suggested possible psychoactive effects in animal studies. As an auxin, ANA influences various physiological processes in plants, making it a crucial subject of interest among botanists and agricultural scientists.
In terms of environmental considerations, some studies indicate that while ANA can optimize crop yield, there may be unintended consequences when utilized indiscriminately. This highlights the need for balance as we exploit its benefits.
Research Objectives and Hypotheses
The primary aim of current research is to elucidate the mechanisms by which alpha naphthyl acetic acid affects plant growth and development. A secondary goal is to explore its potential ramifications in other fields, such as pharmacology.
To this end, several hypotheses have emerged:
- Hypothesis 1: ANA significantly promotes cell division in plant tissue.
- Hypothesis 2: Exposure to ANA influences behavioral patterns in certain animal studies.
- Hypothesis 3: Long-term applications of ANA affect soil health and ecosystem balance.
By testing these hypotheses, scientists aim to deepen our understanding of alpha naphthyl acetic acid and navigate the complexities of its use in various applications.
Methodology
Study Design and Approach
Research on alpha naphthyl acetic acid employs a range of methodologies, often integrating both laboratory and field studies. Laboratory experiments generally focus on controlled environments to isolate the compoundβs effects on plant growth and cellular activity.
Field studies aim to validate laboratory results, allowing researchers to assess how environmental variables impact ANAβs effectiveness. This dual approach ensures that findings are robust and applicable to real-world contexts.
Data Collection Techniques
Data collection for studies involving alpha naphthyl acetic acid can take various forms:
- Quantitative measures: This includes standard growth metrics such as height, leaf number, and biomass weight of treated plant samples.
- Qualitative observations: Research often incorporates visual assessments of plant health and vigor.
- Behavioral assessments in animal studies: Observations may focus on changes in activity levels or other behaviors post-exposure to ANA.
Collating data using these methods enables a comprehensive analysis of alpha naphthyl acetic acidβs properties and effects, laying the groundwork for future research implications and applications.
Chemical Structure of Alpha Naphthyl Acetic Acid
Understanding the chemical structure of alpha naphthyl acetic acid is essential for both academic and practical applications. The molecular arrangement and functional groups influence its properties, as well as its interaction with other compounds. A detailed exploration of this structure lays the groundwork for further discussions on its synthesis and applications, impacting agricultural practices and potential pharmacological uses.
Molecular Formula and Characteristics
Alpha naphthyl acetic acid has the molecular formula C(_12)H(_10)O(_2). This formula reveals key characteristics:
- Carbon Backbone: It consists of 12 carbon atoms forming a stable hydrocarbon structure, which is vital for its function as a growth regulator in plants.
- Presence of Functional Groups: The functional groups present β specifically the carboxylic acid group (βCOOH) β confer specific chemical properties, such as solubility in water and its role in biochemical interactions.
- Physical Properties: Typically, this compound appears as a white crystalline solid at room temperature, indicating a certain level of stability, which is critical when considering application in various environments.
The distinctive structure also allows it to function effectively in modulating plant growth processes. The acid's molecular shape is conducive to its interaction with plant cellular mechanisms, making it a credible choice in agricultural chemistry.
Isomeric Forms and Properties
Isomerism in alpha naphthyl acetic acid offers insight into how variations in molecular arrangement can lead to differing properties. Although it primarily exists as a single form, its potential for isomeric configurations can contribute to varied biological activities and solubility. Key points to note include:
- Geometric Isomers: This compound does not exhibit geometric isomerism due to the single bonds present. However, any variations in the structure might lead to differential interaction within plant systems.
- Optical Isomers: While alpha naphthyl acetic acid doesn't usually show optical activity, understanding this concept is vital since such characteristics are integral in many biochemical applications.
- Solubility Characteristics: Depending on slight variations that can be conjured in laboratory settings, the solubility in polar versus non-polar solvents can be altered, thus influencing the compound's usability in various formulations.
Synthesis of Alpha Naphthyl Acetic Acid
The synthesis of alpha naphthyl acetic acid is fundamental for its utilization in various sectors, particularly in agriculture and pharmacology. Understanding how to synthesize this compound is crucial as it paves the way for exploring more advanced applications and functionality of alpha naphthyl acetic acid. The methods of synthesis not only influence the quality of the resulting product but also have implications for production efficiency, cost effectiveness, and environmental impact.


When looking at the synthesis, it's important to delve into both traditional methods as well as greener alternatives. The traditional approaches have laid the groundwork, while innovative techniques focusing on sustainability are becoming increasingly pertinent in todayβs research landscape.
Traditional Synthesis Methods
Traditional synthesis methods of alpha naphthyl acetic acid typically involve several steps, with a majority of processes relying on well-established synthetic routes. A typical method starts with performing acylation reactions on naphthalene or alpha-naphthol. Hereβs a brief look at a classic approach:
- Starting Materials: Generally, the synthesis utilizes naphthalene or alpha-naphthol, which are widely available in the organic synthesis realm.
- Formation of Acetic Acid Derivatives: Through Friedel-Crafts acylation, these naphthalene derivatives are converted into corresponding substituted forms that contain acetic acid.
- Purification: Post-reaction, the resulting compound undergoes purification techniques like recrystallization or distillation to ensure high purity.
The traditional synthesis is mainly known for its efficiency, but this often comes at a cost of utilizing harsh chemicals and generating waste.
Despite the reliability of these methods, there are growing concerns about environmental repercussions, which drive the need for more sustainable alternatives.
Green Chemistry Approaches
With the increasing emphasis on sustainability, the field has seen a significant shift towards green chemistry approaches in synthesizing alpha naphthyl acetic acid. These methods not only aim to reduce hazardous substances but also enhance operational efficiency in the lab.
Key aspects of green chemistry in this context include:
- Utilizing Non-Toxic Reagents: Many methods now prioritize using safer reagents that lessen negative environmental impacts.
- Employing Renewable Resources: Innovative processes that focus on leveraging bio-based materials instead of fossil fuels show promise.
- Minimizing Waste Production: Techniques such as one-pot synthesis reduce the number of steps and consequently lower the waste generated.
Some researchers have explored microwave-assisted synthesis, which is considered a green method due to its ability to shorten reaction times and improve yields while using less energy.
In summary, the synthesis of alpha naphthyl acetic acid is not just a step in product formation; it encapsulates significant chemical innovation and a tangible commitment to sustainability. The approaches we choose during this synthesis will have ripple effects throughout the compoundβs lifecycle, influencing both its application and the health of our environment.
Mechanism of Action in Plant Growth Regulation
The role of alpha naphthyl acetic acid (ANA) in plant growth regulation is crucial, as it serves as a growth regulator that influences various physiological processes. Understanding its mechanism of action can shed light on innovative agricultural strategies and better crop management practices. The effects of ANA stretch far beyond mere growth stimulation; it intricately interacts with plants on a cellular level. This section focuses on two primary aspects how it influences cell division and elongation, and its interactions with other plant hormones.
Influence on Cell Division and Elongation
Cell division and elongation are fundamental processes in plant growth and development. Alpha naphthyl acetic acid acts on plant cells by promoting these processes, thus facilitating not only growth but also the overall health and resilience of the plant.
When ANA is applied to plant tissues, it enhances cell division in meristematic regions, particularly in roots and shoot tips. This effect can be attributed to its role in regulating auxin levels within plant cells. Auxins are a group of hormones imperative for the elongation of plant cells. Research shows that ANA, as a synthetic auxin, mimics the natural hormones, thus promoting not just division but also elongation of cells.
The results can often be seen in the field. For instance, when crops are treated with alpha naphthyl acetic acid, one may observe a substantial increase in the length of stems and branches. This effect can influence plant architecture and overall yield. Not only does a higher rate of cell division lead to more robust plant structures, but it also contributes to enhanced nutrient uptake and stress resistance.
"Using alpha naphthyl acetic acid in agricultural practices can lead to noticeable improvements in both the vigor and productivity of crops."
Additionally, these growth-promoting effects can extend to increased root development. A broader root system enhances the plant's ability to absorb water and nutrients, making it better equipped to survive adverse conditions such as drought or nutrient-poor soils.
Interactions with Plant Hormones
The interplay between alpha naphthyl acetic acid and plant hormones is complex yet fascinating. As mentioned earlier, ANA functions similarly to natural auxins. It does not act in isolation; instead, it interacts with a suite of other hormones, including cytokinins and gibberellins, affecting various growth responses.
For example, cytokinins are known for promoting cell division and are often present in conjunction with auxins to regulate plant growth. The balance between these hormones is vital. If applied appropriately, ANA can spur the effects of cytokinins, leading to enhanced growth outcomes. Conversely, an imbalance may hinder development.
Moreover, the relationship between ANA and gibberellins illustrates how different growth pathways are connected. Gibberellins mainly stimulate stem elongation and seed germination; when used alongside ANA, the combined effect can produce more pronounced growth results than either hormone alone. Hence, the science behind hormone interaction underscores the need for careful management when utilizing alpha naphthyl acetic acid in agronomy.
For further reading, researchers can refer to Wikipedia, or explore studies at Britannica for more detailed discussions about plant hormones and their interactions.
Applications in Agriculture
The applications of alpha naphthyl acetic acid (ANA) in agriculture are nothing short of groundbreaking. Its primary role as a growth regulator underlines the significance of this compound in enhancing agricultural productivity and sustainability. With growing concerns about food security and environmental impacts, understanding how ANA functions is vital for farmers, researchers, and policymakers alike. This section will delve into two crucial aspects of alpha naphthyl acetic acid's applications in agriculture: its use as a growth regulator and its impact on crop yield and quality.
Use as a Growth Regulator
Alpha naphthyl acetic acid has found its niche as a potent growth regulator in various crops. The compound plays a pivotal role in manipulating plant growth processes, affecting not just the growth rate, but also influencing several key physiological functions.
- Cell Division and Elongation: ANA promotes cell division and elongation through its role in auxin-like activities. It effectively encourages roots and shoots to develop, ensuring that plants grow more robustly.
- Delayed Senescence: Another fascinating aspect is how this compound can delay senescence in plants, prolonging the vegetative stage. This prolongation allows for increased photosynthetic activity, ultimately leading to improved biomass production.
- Practical Application: Farmers often apply alpha naphthyl acetic acid in conjunction with other growth substances for optimal effects. The balance of nutrient supply, water availability, and environmental conditions can dictate the success of applying growth regulators like ANA. Many agricultural practices have adopted its use, with results showing promising improvements in growth efficiency and health of the crops.


Impact on Crop Yield and Quality
The overarching goal in agriculture remains the drive for higher crop yields and superior quality products. Alpha naphthyl acetic acid presents numerous benefits in this domain, influencing both quantity and quality of agricultural outputs.
- Enhanced Crop Yield: Numerous studies have illustrated the correlation between ANA application and increased crop yield. For instance, applying it to cereals and various fruits has yielded significant increases in final production. This increase can often be attributed to improved root system development, allowing plants to uptake water and nutrients more effectively.
- Quality of Produce: Besides boosting yields, alpha naphthyl acetic acid also enhances the quality of crops. Better cellular growth leads to denser and more nutritious fruits. In many cases, the use of this compound has resulted in enhanced taste, color, and texture of produce, which can also improve market demand and economic viability for farmers.
- Sustainability Considerations: Ultimately, the use of alpha naphthyl acetic acid is becoming integral in developing sustainable agricultural practices. As the global population grows, finding ways to improve yield without the excessive use of chemicals or land is critical. The potential of ANA to maximize plant growth can contribute to achieving this essential balance.
"With the ever-increasing demand for food, understanding and utilizing growth regulators like alpha naphthyl acetic acid becomes crucial in modern agriculture."
As Indonesia or China, farmers are increasingly looking for safe, effective methods to optimize their agricultural practices. Understanding the usage of alpha naphthyl acetic acid and acknowledging its role can pave the way for more resource-efficient farming strategies, thus ensuring food security for the future. In this light, alpha naphthyl acetic acid not only represents a scientific marvel but also an agricultural necessity.
Pharmacological Applications
The pharmacological applications of alpha naphthyl acetic acid (ANAA) are extensive and should not be underestimated. As a compound with potential neuroactive properties, it commands attention not just in the realm of agriculture but also in the field of medicine. Understanding these applications exposes its multifaceted role in both enhancing plant growth and exploring new horizons in human health management.
Potential Neuroactive Effects
Research suggests that ANAA exhibits neuroactive effects that could have significant implications in medicinal chemistry. Early animal studies have indicated that it may influence neurotransmitter pathways, particularly by modulating dopaminergic and serotonergic systems. This modulation could pave the way for developing treatments focused on neurological conditions such as depression and anxiety.
Some key points regarding neuroactive effects include:
- Hormonal Interactions: The compoundβs ability to interact with hormonal pathways raises the possibility of adjusting neurochemical imbalances.
- Behavioral Changes: Observations in animal models have highlighted changes in behavior, suggesting that it may possess anxiolytic or even antidepressant-like properties.
- Targeting Neurotransmission: By altering neurotransmission dynamics, ANAA may serve as a candidate for further studies into neurodegenerative diseases.
This line of exploration is promising. As researchers continue to peel back the layers surrounding ANAAβs effects, there may be groundbreaking applications that could reshape current therapeutic approaches.
Role in Disease Treatment
The role of alpha naphthyl acetic acid in disease treatment is a developing area of interest. Although still mostly in the research phase, it holds potential for addressing a variety of health issues. Significant attention is being directed toward its anti-inflammatory effects and possible neuroprotective properties, which could influence the treatment strategies for conditions such as Alzheimerβs disease, Parkinsonβs disease, and other neurodegenerative disorders.
Important aspects of ANAAβs role in disease treatment include:
- Anti-Inflammatory Properties: Preliminary studies indicate that ANAA may help mitigate inflammatory responses in neural tissue, which is crucial for managing conditions associated with chronic inflammation.
- Neuroprotection: By protecting neuronal cells from oxidative stress, it could offer strategies for slowing disease progression.
- Combination Therapies: Integrating ANAA with existing drug regimens may enhance therapeutic outcomes. The potential to synergize with more conventional treatments can lead to innovative approaches in patient care.
"As we stand on the threshold of new discoveries, the multifaceted roles of alpha naphthyl acetic acid could redefine therapeutic landscapes in neurology and beyond."
Environmental Considerations
In the realm of chemical compounds, alpha naphthyl acetic acid (ANA) stands out not only for its versatility but also for the environmental considerations it entails. The significance of this topic cannot be underestimated as it intertwines the applications in agriculture and pharmacology with the broader impacts on our ecosystems. The growing necessity for sustainable practices has put compounds like ANA under scrutiny, leading to important discussions about their ecological footprint and long-term viability.
Impact on Soil Ecology
Alpha naphthyl acetic acid is primarily known as a growth regulator in plants, yet its influence extends into the soil ecosystem as well. When applied to agricultural land, grading the soil balance is fundamental. The use of ANA can help enhance root development and overall plant health. For instance, improved root systems not only support plant growth but also facilitate better nutrient uptake, which can lead to healthier crops and reduced use of fertilizers.
However, the application of such chemical compounds necessitates careful considerations. One potential concern is the risk of bioaccumulation or modification of the local soil microbiome. This refers to the communities of microorganisms that dwell beneath our feet, playing a crucial role in nutrient cycling and soil health. Introducing synthetic auxins, like ANA, may disrupt this delicate balance if not managed properly.
"Ecosystems thrive on balance; introducing external factors can tip the scale in unexpected ways."
Understanding how alpha naphthyl acetic acid affects soil microorganisms can lead to improved agricultural practices. Research into the symbiosis between plants and microbes may reveal optimal levels of ANA usage that enhance crop yield without harming soil health.
Regulatory Issues and Safety
The growing awareness of environmental safety has paved the way for regulatory frameworks that govern the use of agricultural chemicals, including alpha naphthyl acetic acid. Different regions have various standards, and it's crucial to comply with local and national regulations to ensure safe application. For example, in the United States, the Environmental Protection Agency (EPA) closely monitors the registration and use of such chemical growth regulators to minimize potential risks to humans, wildlife, and the environment.
Additionally, safety assessments encompass both the short-term and long-term effects of chemicals like ANA. This includes evaluation of how they persist in the environment and their potential to cause harm if they leach into water supplies or adversely affect non-target species. The Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) provides guidelines on how to properly assess and manage these substances to ensure that they do not pose a significant threat.
Moreover, the rise of green chemistry principles emphasizes designing chemicals that are less harmful to the environment. These principles advocate for innovative approaches to synthesis and application in order to reduce toxicity and environmental impact, thereby aligning the use of alpha naphthyl acetic acid with sustainable agricultural practices.
Ultimately, while alpha naphthyl acetic acid offers valuable applications, its role must be carefully evaluated against ecological risks and regulatory compliance. A balanced approach ensures that we can reap the benefits of this compound while safeguarding our environment for future generations.
Recent Research and Advances


Recent research on alpha naphthyl acetic acid (ANA) unveils its multifaceted role, stretching far beyond its traditional applications. Scientists and researchers are actively engaged in exploring novel pathways and practical uses for this compound, particularly in agricultural and biomedical fields. The significance of such studies lies in the potential innovations that could enhance crop yields, improve plant health, and offer therapeutic options in medicine. The exploration of alpha naphthyl acetic acid is cutting-edge, addressing pressing challenges in food security and health, while being mindful of environmental implications.
Innovative Applications in Biomedicine
Alpha naphthyl acetic acid has garnered attention for its potential in the realm of biomedicine, mainly because of its influences observed in various physiological processes. Some recent studies have indicated that it may play a role in regulating neurochemical pathways. For example, in specific animal models, it has been suggested that ANA can enhance synaptic plasticity, a process pivotal in learning and memory. This could open doors to its use in therapies aimed at neurodegenerative diseases, where cognitive functions decline over time.
Additionally, researchers are investigating how ANA interacts with other compounds to elicit beneficial responses in human cells, thereby offering alternative therapeutic avenues for treatment-resistant conditions.
Key highlights of its biomedical applications include:
- Potential in enhancing synaptic connections, offering hopes in cognitive decline therapies.
- Role in modulating neurotransmitter levels, which may provide insights into treating mood disorders.
These findings represent just the tip of the iceberg, indicating a blossoming interest in integrating alpha naphthyl acetic acid into biomedical research frameworks.
Emerging Trends in Agricultural Research
The agricultural sector is witnessing a renaissance of sorts, with recent studies honing in on alpha naphthyl acetic acid as a crucial growth regulator. As farming practices evolve, the necessity for sustainable and efficient farming methods becomes paramount. Research is focusing on how ANA can be utilized for developing resilient crop varieties that withstand environmental stressors such as drought or salinity. This is especially important in the face of climate change, which poses threats to agricultural outputs worldwide.
Key areas of investigation include:
- Enhancing root development: Studies have shown that alpha naphthyl acetic acid can stimulate root elongation, leading to better nutrient uptake and plant vigor.
- Increasing stress tolerance: Identifying the pathways through which ANA mediates stress responses is a hot topic, as it may allow for the engineering of more robust crop varieties.
Furthermore, with the rise of precision agriculture, research is also delving into the optimal doses and application methods of alpha naphthyl acetic acid, ensuring that agricultural practices not only yield benefits but do so in an environmentally sustainable manner. This is where the intersection of technology and biology lies, promising farmers not just higher outputs but also healthier soils.
Recent findings suggest that innovative uses of alpha naphthyl acetic acid could revolutionize both agriculture and medicine, making it a compound worth closely monitoring.
Future Directions in Alpha Naphthyl Acetic Acid Research
The investigation into alpha naphthyl acetic acid (ANA) has gathered momentum in both the agricultural and biomedical fields. As researchers peel back the layers of its potential, they are led to explore novel approaches and applications. These future directions in research are not just academic; they hold tangible benefits that could ripple across various sectors. The deep curiosity surrounding ANA is not merely about its past usage but about what lies ahead and how this compound can help tackle pressing global issues.
Biotechnological Innovations
In recent years, biotechnology has become a linchpin in the development of sustainable agricultural practices. The exploration of alpha naphthyl acetic acid through biotechnological lenses opens doors to innovative solutions, particularly in genetic engineering to enhance plant growth. Scientists are looking into ways to create genetically modified organisms that can utilize ANA more effectively, maximizing its growth-promoting properties.
- Enhanced Crop Varieties: Research into the genetic enhancement of crops to improve their sensitivity to ANA is underway. This could lead to variations of staple crops that require less overall fertilizer while achieving higher yields, addressing food security issues.
- Microbial Interactions: Leveraging beneficial microbes in soil that can inherently interact with ANA is being examined. Such microbes can transport hormonal signals to plants, leading to better growth responses.
- Nano-encapsulation Techniques: The delivery of ANA through nanotechnology is another area gaining attention. Creating nano-formulations can ensure the sustained release of the compound, minimizing waste and optimizing its effectiveness.
The application of these biotechnological innovations presents a wealth of opportunities, paving the way for research that keeps in step with ecological norms while increasing productivity.
Integrated Approaches for Sustainable Use
As the dialogue around sustainability intensifies, integrated approaches to the use of alpha naphthyl acetic acid are essential. It is no longer about treating plants with growth regulators in isolation; rather, there's a growing focus on how these substances fit into bigger ecological systems.
- Crop Rotation and Use of Local Strains: Implementing crop rotation strategies and utilizing native species alongside ANA could offer dual benefits: enhanced biodiversity and improved use of the compound.
- Soil Health Monitoring: Future research should aim to understand how the application of ANA affects soil microorganisms. There are questions about its longevity in the soil and how it influences natural soil health dynamics.
- Collaborative Research Frameworks: Engaging cross-disciplinary teams that involve agronomists, ecologists, and chemists will result in more holistic studies of ANA's impacts. Such collaboration could yield insights on optimizing its application while safeguarding environmental integrity.
As we look forward, these integrated methods are not just practical solutions but represent a sophisticated understanding of the interactions between agricultural practices and ecological balance. The effective use of alpha naphthyl acetic acid will likely hinge on our ability to innovate responsibly and leverage modern technology thoughtfully.
"The future of research on alpha naphthyl acetic acid is illuminated by innovation and sustainability, leading to practices that not only produce food but also protect our ecosystems."
Closure
In the exploration of alpha naphthyl acetic acid, it becomes abundantly clear how pivotal this compound is across various scientific realms. From its chemical structure that allows it to function effectively as a plant growth regulator to its intriguing pharmacological properties, this substance showcases versatility that is truly remarkable. The significance of understanding alpha naphthyl acetic acid cannot be underestimated, as its applications in agriculture can lead to improved crop yields and enhanced food quality. Furthermore, the potential neuroactive effects open avenues in medical research, potentially driving forward innovations in treatment strategies for various diseases.
Significance in Modern Science
Alpha naphthyl acetic acid stands at the intersection of agroscience and pharmacology. In agricultural practices, its ability to regulate growth signals a shift towards more controlled farming techniques. This isnβt just a step forward for farmers aiming for efficiency, but a wider acknowledgment of how synthetic compounds can work in harmony with nature to boost sustainability.
Moreover, the pharmacological implications highlight its role beyond just plant systems. Research exploring its potential in treating neurological disorders hints at a future where substances derived from seemingly mundane sources can offer groundbreaking treatments. This speaks volumes about the interconnectivity of chemistry with biology, reminding us of the hidden potentials awaiting discovery.
Call for Continued Research
The numerous applications of alpha naphthyl acetic acid illuminate the pressing need for continued research. As scientists delve deeper, the long-term impacts on human health and environmental sustainability must be considered. The ongoing evolution of agricultural requirements and the rise of eco-friendly practices necessitate a holistic approach to research.
Continued investigation into the applications and effects of alpha naphthyl acetic acid is crucial for not only optimizing agricultural output but also ensuring the safety and health of ecosystems.
It is of utmost importance that future studies address gaps in existing knowledge, especially regarding toxicity, ecological impacts, and optimal application levels. Various stakeholders, from farmers to environmentalists, should be engaged in dialogues that foster collaborative efforts in research and development. More rigorous and innovative studies can lead to discoveries that further enhance the beneficial uses of this compound while addressing regulatory and safety concerns, ultimately fostering a more sustainable future connected to scientific inquiry.
For a thorough understanding of these aspects and the significance they hold in modern societal contexts, researchers and practitioners alike must embark on this journey of discovery, exploring the multifaceted roles of alpha naphthyl acetic acid.