Synthesis of phenylacetates using aluminium-exchanged montmorillonite clay catalyst

Liquid phase esterification of phenylacetic acid with phenol and substituted phenols has been investigated over montmorillonite clay exchanged with H + - Al 3+ - and aluminium polyhydroxy oligomer cations. Among the catalysts studied, Al 3+ - montmorillonite dried at 100°C showed 67 conversion, while the same catalyst dried at 200deg;C showed reduced conversion of 36. Al 3+ - montmorillonite dried at 400°C and montmorillonite exchanged with aluminium polyhydroxy oligomer cations dried at 100°C and calcined at 500°C failed to bring about the reaction. Effects of mole ratio of reactants, reaction period and catalyst amount on yield of the ester and catalyst regeneration are also investigated. Esterification of phenylacetic acid with phenol, cresols, nitrophenols and resorcinol has been carried out in the presence of montmorillonite clay exchanged with H +-ions, Al 3+-ions and polyhydroxy oligomer cations of Al. Na +-montmorillonite (raw clay) was inactive, H +- and Al 3+-montmorillonites, dried at 100°C, showed 52 and 67 conversions to ester, respectively, upon refluxing the phenylacetic acid (20 mmol) and p-cresol (40 mmol) for 6 h. While Al 3+- montmorillonite dried at 200°C showed a conversion of 36 the same catalyst when dried at 400°C showed no conversion. Montmorillonite exchanged with aluminium polyhydroxy oligomers dried at 100°C and calcined at 500°C to get pillared clay (d 0 0 1=17.5 à ) failed to bring about the esterification. Effect of concentration of reactants, amount of catalyst and the reaction time on the yield of p-cresyl phenylacetate has been investigated. The esterification of phenylacetic acid with phenol and substituted phenols like m-cresol, o-cresol, p-nitro phenol and o-nitro phenol showed reduced yield due to steric factors. The activity of the clay catalyst after regeneration has also been studied. © 2004 Published by Elsevier B.V

Differences in symptom severity and quality of life among patients with cancer using conventional therapies with/without herbal medicines in Uganda: a cross-sectional study

Objective: Patients with cancer experience numerous symptoms related to cancer and treatment side effects that reduce their quality of life (QOL). Although herbal medicine (HM) is used to manage such symptoms by patients in sub-Saharan Africa, data on patients perceived clinical outcomes are limited. We compared differences in QOL and symptom severity between patients with cancer using HM plus conventional therapies (i.e., chemotherapy, hormonal therapy, radiotherapy, surgery) and those using conventional therapies alone. Methods: This cross-sectional study included patients with cancer aged \u3e18 years who were consecutively sampled and completed a researcher-administered questionnaire between December 2022 and January 2023. Specifically, data was collected using The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) and the MD Anderson Symptom Inventory for Traditional Chinese Medicine (MDASI-TCM). Data were analyzed using descriptive statistics and chi-square and logistic regression analyses. Results: Of 400 participants (67.5% female), 49% (n=195) used HM plus conventional therapies and 51% (n=205) used conventional therapies alone. Most participants were aged \u3e38 years (73.3%; median age 47 years). A univariate analysis showed the HM plus conventional therapies group had better mean scores for most QOL and symptom severity measures than the conventional therapies alone group. However, only role functioning significantly differed (p=0.046) in the bivariate analysis. There were no statistically significant differences between the two groups after confounder adjustment for all others measures of symptom severity and QOL. Conclusion: HM plus conventional therapies may offer minimal benefits or differences for clinical outcomes among patients with cancer. However, our findings have clinical, research, and public health implications for Uganda and other sub-Saharan African settings

The meaning of caring for patients with cancer among traditional medicine practitioners in Uganda: A grounded theory approach

Traditional medicine practitioners (TMPs) are a critical part of healthcare systems in many sub-Saharan African countries and play vital roles in caring for patients with cancer. Despite some progress in describing TMPs’ caring experiences in abstract terms, literature about practice models in Africa remains limited. This study aimed to develop a substantive theory to clarify the care provided by TMPs to patients with cancer in Uganda. This study adhered to the principal features of the modified Straussian grounded theory design. Participants were 18 TMPs caring for patients with cancer from 10 districts in Uganda, selected by purposive and theoretical sampling methods. Researcher-administered in-depth interviews were conducted, along with three focus group discussions. Data were analyzed using constant comparative analysis. The core category that represented TMPs’ meaning of caring for patients with cancer was “Restoring patients’ hope in life through individualizing care.” TMPs restored patients’ hope through five main processes: 1) ensuring continuity in the predecessors’ role; 2) having full knowledge of a patient’s cancer disease; 3) restoring hope in life; 4) customizing or individualizing care, and 5) improving the patient’s condition/health. Despite practice challenges, the substantive theory suggests that TMPs restore hope for patients with cancer in a culturally sensitive manner, which may partly explain why patients with cancer continue to seek their services. The findings of this study may guide research, education, and public health policy to advance traditional medicine in sub-Saharan Africa

Prevalence of the Use of Herbal Medicines among Patients with Cancer: A Systematic Review and Meta-Analysis

Background: Although herbal medicines are used by patients with cancer in multiple oncology care settings, the magnitude of herbal medicine use in this context remains unclear. )e purpose of this review was to establish the prevalence of herbal medicine use among patients with cancer, across various geographical settings and patient characteristics (age and gender categories). Methods: Electronic databases that were searched for data published, from January 2000 to January 2020, were Medline (PubMed), Google Scholar, Embase, and African Index Medicus. Eligible studies reporting prevalence estimates of herbal medicine use amongst cancer patients were pooled using random-effects meta-analyses. Studies were grouped by World Bank region and income groups. Subgroup and meta regression analyses were performed to explore source of heterogeneity. Results: In total, 155 studies with data for 809,065 participants (53.95% female) met the inclusion criteria. Overall, the pooled prevalence of the use of herbal medicine among patients with cancer was 22% (95% confidence interval (CI): 18%–25%), with the highest prevalence estimates for Africa (40%, 95% CI: 23%–58%) and Asia (28%, 95% CI: 21%–35%). )e pooled prevalence estimate was higher across low- and middle-income countries (32%, 95% CI: 23%–42%) and lower across high-income countries (17%, 95% CI: 14%–21%). Higher pooled prevalence estimates were found for adult patients with cancer (22%, 95% CI: 19%–26%) compared with children with cancer (18%, 95% CI: 11%–27%) and for female patients (27%, 95% CI: 19%–35%) compared with males (17%, 95% CI: 1%–47%). Conclusion: Herbal medicine is used by a large percentage of patients with cancer use. The findings of this review highlight the need for herbal medicine to be integrated in cancer care

Ethnobotanical survey of medicinal plants used in the management of cancer in Uganda

Introduction: Patients with cancer in Africa embrace the use of herbal medicine more than anywhere else in the world. This study identified and documented medicinal plant species used to manage cancer in ten (10) districts of Uganda. Methods: An ethnobotanical survey was conducted between October 2021 and January 2022. In total, 18 (out of 55) traditional medicine practitioners (TMPs) having more than 10 years of experience in managing patients with cancer were interviewed using a semi-structured questionnaire. Data were analysed using descriptive statistics. The Relative frequency of citation (RFC) and Family importance value (FIV) indices were also computed. Results: We identified 121 plant species, belonging to 55 families, with the most common families being the Fabaceae (20 species, FIV = 0.119), Asteraceae (13 species, FIV = 0.131), and Euphorbiaceae (eight species, FIV = 0.079). The plant parts most commonly used were leaves (39.3%) and roots (12.9%). The most frequently cited plants were: Hoslundia opposita Vahl (RFC = 0.44), followed by Aspilia africana (Pers.) C.D. Adams (RFC = 0.33), Spathodea nilotica Seem (RFC = 0.33), Annona muricata L. (RFC = 0.33, Prunus africana (Hook.f.) Kalkman (RFC = 0.28), Acacia hockii De Wild (RFC = 0.28), Bidens pilosa L. (RFC = 0.28), and Carica papaya L (RFC = 0.22). The most common method of plant preparation and administration was the decoction (69.2%) and oral (86.7%) route, respectively. Conclusions: Although most plants used by TMPs have the potential to generate leads for chemo-preventive cancer medicines, they remain unexplored. This study provides a lead to explore the potential of traditionally used plants for the management of cancer through pre-clinical and clinical research

Synthesis of ester components of spermaceti and a jojoba oil analogue catalyzed by acid activated Indian bentonite under microwave irradiation

Acid activated Indian bentonite (AAIB) is an excellent catalyst for the esterification of long chain fatty acids with long chain alcohols. The ester constituents of spermaceti (whale wax) and an analogue of jojoba oil are obtained when the reactants with catalyst are exposed to microwave irradiation under solvent-free conditions. The Indian bentonite is used for such a reaction for the first time. The procedure is essentially pollution-free as virtually no waste material is produced. Esters can also be synthesized by solvent-free alkylations of carboxylic anions under microwave irradiation. A few solventfree alkylations of carboxylic anions have been reported using tetrabutylammonium bromide (TBAB) as a phase transfer catalyst under microwave irradiation

Synthesis of ester components of spermaceti and a jojoba oil analogue catalyzed by acid activated Indian bentonite under microwave irradiation

377-381Acid activated Indian bentonite (AAIB) is an excellent catalyst for the esterification of long chain fatty acids with long chain alcohols. The ester constituents of spermaceti (whale wax) and an analogue of jojoba oil are obtained when the reactants with catalyst are exposed to microwave irradiation under solvent-free conditions. The Indian bentonite is used for such a reaction for the first time. The procedure is essentially pollution-free as virtually no waste material is produced. Esters can also be synthesized by solvent-free alkylations of carboxylic anions under microwave irradiation. A few solvent-free alkylations of carboxylic anions have been reported using tetrabutylammonium bromide (TBAB) as a phase transfer catalyst under microwave irradiation

Acid activated indian bentonite, an efficient catalyst for esterification of carboxylic acids

The preparation, characterization, and catalytic properties of acid activated Indian bentonite (AAIB) are reported. AAIB has been characterized by XRD (basal spacing, 15.05 à ), specific surface area (273 m 2/g), pore volume and pore diameter using BET method, TGA, SEM, and surface acidity by n-butylamine back titration method and infrared spectroscopy using pyridine as a probe molecule. The activity of Montmorillonite K10, ZrO 2, S-ZrO 2, p-toluenesulfonic acid (p-TSA), Indian bentonite (IB), and AAIB was investigated by the esterification of p-cresol with stearic acid. Among the catalysts, AAIB was found to be more active. The esterification of various carboxylic acids with phenols and alcohols was studied on AAIB to obtain corresponding esters in good yields. The regeneration and reusability of AAIB has also been investigated. © 2008 Springer Science+Business Media, LLC