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A fluorination-induced intramolecular cyclization for the synthesis of fluoro-substituted spiro-1,3-oxazine and spiro-1,3-thiazine derivatives is described. N -(2-(Cyclohex-1-en-1-yl)ethyl)benzamide and benzothioamide are used as the substrates, and the cationic fluorinating agent Selectfluor works as the fluoride source. The reaction yields a single diastereomer. The scope of this regioselective fluorination reaction is established by preparing thirty different spirooxazine and spirothiazine derivatives.

An interesting self-coupling/cyclization of 5-aminopyrazoles is revealed, which provides a variety of pyridazine cores in reasonable yields. In this reaction, C(sp 2 )-C(sp 2 ) and N-N bond formation occurs simultaneously in one reaction vessel. The photophysical properties of the synthesized compounds were also studied and some of them exhibited fluorescence properties with good quantum yields. A radical mediated reaction mechanism is proposed with the help of control experiments.

This review article focuses on the α-functionalization of acetophenones involving Kornblum oxidation and C-H functionalizations. Although various other strategies, such as classical approaches, enamine approaches and umpolung strategy are also known for this functionalization, here we discuss mainly the Kornblum oxidation approach and C-H functionalization strategy as they have advantages over the others. In Kornblum oxidation, the reaction uses iodine and dimethylsulfoxide and proceeds through the formation of arylglyoxal as the key intermediate. In C-H functionalization, the reaction requires metal, or metal-free catalyst, and generates radical intermediate in most cases. α-Functionalization of acetophenones is very important because of their huge applications in the synthesis of various natural products and pharmaceuticals and, therefore, a number of research articles have been published in this area. However, no review articles are available so far. In this article, we present a succinct discussion of various important and novel reactions, along with their mechanisms, published since 2012 to date. We believe that this first review article in this field will give readers one-stop information on this topic and encourage further intriguing work in this area., (© 2021. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Background: Trinakantamani Pishti (TMP) is a cardio-tonic ( Hridya ), styptic ( Rakta Stambhaka ), astringent ( Kashaya ) formulation frequently used in varieties of bleeding disorders such as bloody diarrhea ( Raktatisaara ), Raktarsha (bleeding piles), and disorders of excessive menstruation ( Atyartava ). Still, no published data is available regarding its characterization., Aim: To generate a fingerprint for raw and processed TMP using sophisticated instrumental techniques to assess antimicrobial activity of TMP., Materials and Methods: Three samples of TMP were prepared using the standard reference method. Characterization of TMP was carried out by Fourier-transform infrared spectroscopy (FTIR), energy dispersive X-ray analysis (EDEX) with scanning electron microscopy, powder X-ray diffraction (XRD) . Antibacterial activity was carried out by the well-diffusion method., Results: Analysis by scanning electron microscope revealed maximum particle size <5 μm and <3 μm in the raw sample and TMP, respectively. Minimum particle size in TMP ranges from 1 to 2 μm and 701 nm. EDEX analysis shows carbon and oxygen as major constituents while Na, Mg, Ca, Si, Fe, and S were present in traces. XRD pattern indicates the amorphous nature of the drug, while FTIR analysis reveals the presence of functional groups such as O-H, CO2, C = O, C-N, N-H. Heavy metals, total microbial count, and microbial limit test were found to be under permissible limits. Anti-microbial study against tested pathogens Staphylococcus aureus , Escherichia coli , Pseudomonas aeruginosa and Salmonella typhimurium did not show any effect of TMP., Conclusion: The results of EDEX study showed that Pishti samples have the small particle size i.e., 701nm than the raw i.e., 1-2 μm, which may facillitate absobtion of drug into the body. All heavy metals in the samples were within the permissible limit. Carbon, hydrogen and oxygen are the chief elements of drug which confirms similarity to the Amber , Since the present work is the first published literature on characterization and anti-microbial study on TMP, the outcome can be considered as fingerprint for the drug prepared using the mentioned reference method., Competing Interests: There are no conflicts of interest., (Copyright: © 2022 AYU (An International Quarterly Journal of Research in Ayurveda).)

A highly effective 6-endo dig cyclisation of o-alkynylaldimines to 1,2-dihydroisoquinolines has been described via direct and nitro Mannich condensation using inexpensive and readily available cobalt chloride as catalyst. This strategy provides an effective procedure for the synthesis of substituted 1,2-dihydroisoquinolines derivatives in moderate to high yields. An addition of pronucleophiles, such as nitromethane, acetone and α-hydroxyacetone, to o-alkynylarylaldimines has been achieved via isoquinolinium intermediate.

Recently synthesis of programmable DNA ligands which can regulate transcription factors have increased the interest of researchers on the functional ability of DNA interacting compounds. A series of DNA interacting compounds are being designed which can differentiate between GC and AT rich DNA. In this study, we have studied the specificity of a few novel bisbenzimidazoles having different bi/tri-substituted phenyl rings, with DNA duplexes using spectroscopic methods. This study entails an integrative approach where we combine biophysical methods and molecular dynamics simulation studies to establish suitable scaffolds to target A/T DNA. We have designed a few analogues of Hoechst 33342 viz.; dimethoxy (DMA), trimethoxy (TMA), dichloro (DCA) and difluoro (DFA) functionalities and performed molecular docking of newly designed analogues with biologically relevant AT and GC rich DNA sequences. The docking studies, along with molecular dynamics (MD) simulations of d(ATATATATATATATAT)2, d(GA4T4C)2, d(GT4A4C)2 and GC rich sequence: d(GCGCGCGCGCGCGCGC)2 complexed with DMA, TMA and DFA, showed that these molecules have higher binding affinity towards AT rich DNA. None of these compounds exhibited an affinity to GC rich DNA rather we observed that these compounds destabilize GC rich DNA. The binding was characterized by strong stabilization of the polynucleotides against thermal strand separation in thermal melting experiments. New insights into the molecules binding to DNA have emerged from these studies. All the DNA binding ligands stabilized d(GA4T4C)2 and d(GT4A4C)2 more out of the five oligomers used for the study, suggesting that these ligands bind 'A4T4' and 'T4A4' strongly as compared to 'ATAT' base pairs.

To find out an approach to water quality management through correlation studies between various water quality parameters, the statistical regression analysis for six data points of underground drinking water of different hand pumps at J. P. Nagar was carried out. The comparison of estimated values with W.H.O drinking water standards revealed that water of the study area is polluted with reference to a number of physico-chemical parameters studied. Regression analysis suggests that conductivity of underground water is found to be significantly correlated with eight out of twelve water quality parameters studied. It may be suggested that the underground drinking water quality at J. P. Nagar can be checked very effectively by controlling the conductivity of water. The present study may be treated one step forward towards the water quality management.

Twenty six patients of different types of leprosy were studied for radio active iodine uptake (I131) and serum levels of triiodothyronine (T3), thyroxine (T4) and thyroid stimulating hormone (TSH). None of the patients had clinical evidence of thyroid involvement. No significant difference was found between the values obtained in patients and normals and in different varieties of leprosy.

The serum levels of total immunoreactive insulin (IRI) and proinsulin-like component (PLC) in the fasting state and following the administration of insulin secretagogues in 5 patients with organic hyperinsulinism and age and sex matched normal subjects are reported. Diagnosis of organic hyperinsulinism could be established in all instances on the basis of the inappropriately high total serum IRI levels for the corresponding blood glucose values; such an abnormal relationship was not seen in normal subjects, and was further enhanced by insulin secretagogues. Unrestrained insulin secretion in organic hyperinsulinism was enhanced following the administration of glucose, tolbutamide, glucagon or amino acids; the last 2 stimuli are known to be ineffective in causing insulin secretion in the presence of hypoglycemia in normal subjects. Four patints had insulinomas and one probably had islet cell hyperplasia or abnormal function of islet cells. Chromatography of serum IRI to quantitate PLC is a useful adjunct to the diagnosis of organic hyperinsulinism as in the fasting state the proportion of PLC is always elevated, above the normal range of 5-22%. Following the administration of insulin secretagogues there was pronounced increase in total serum IRI in organic hyperinsulinism but the proportion of PLC generally decreased, suggesting thereby that mojor increase in IRI was due to release of stored granular IRI which is known to have a low proportion of PLC.

Qualitative and quantitative studies of erythropoiesis in 23 patients with hypothyroidism and 21 patients with hyperthryoidism included routine hematologic evaluation, bone marrow morphology, status of serum iron, B12 and folate red blood cell mass and plasma volume by radioisotope methods, erythrokinetics and radiobioassay of plasma erythropoietin. A majority of patients with the hypothyroid state had significant reduction in red blood cell mas per kg of body weight. The presence of anemia in many of these patients was not evident from hemoglobin and hematocrit values due to concomitant reduction of plasma volume. The erythrokinetic data in hypothyroid patients provided evidence of significant decline of the erythropoietic activity of the bone marrow. Erythroid cells in the marrow were depleted and also showed reduced proliferative activity as indicated by lower 3H-thymidine labeling index. Plasma erythropoietin levels were reduced, often being immeasurable by the polycythemic mouse bioassay technique. These changes in erythropoiesis in the hypothyroid state appear to be a part of physiological adjustment to the reduced oxygen requirement of the tissues due to diminished basal metabolic rate. Similar investigations revealed mild erythrocytosis in a significant proportion of patients with hyperthyroidism. Failure of erythrocytosis to occur in other patients of this group was associated with impaired erythropoiesis due to a deficiency of hemopoietic nutrients such as iron, vitamin B12 and folate. The mean plasma erythropoietin level of these patients was significantly elevated; in 4 patients the levels were in the upper normal range whereas in the rest, the values were above the normal range. The bone marrow showed erythyroid hyperplasia in all patients with hyperthyroidism. The mean 3H-thymidine labeling index of the erythroblasts was also significantly higher than normal in hyperthyroidism; in 8 patients the index was within the normal range whereas in the remaining 13 it was above the normal range. Erythrokinetic studies also provided evidences of increased erythropoietic activity in the bone marrow. It is postulated that thyroid hormones stimulate erythropoiesis, sometimes leading to erythrocytosis provided there is no deficiency of hemopoietic nutrients. Stimulation of erythropoiesis by thryoid hormones appears to be mediated through erythropoietin.

Serum and 24-hr urine samples were collected on 2 consecutive days during the first week of each month for 1 yr from eight healthy euthyroid men aged 25-37 yr. The means of minimum and maximum environmental temperature for the 30 days period preceding the sample collection represented the temperature for that month. Total serum thyroxine (T4), triiodothyronine (T3), thyrotropin (TSH), and urinary T3 and T4 were measured by specific radioimmunoassays and serum thyroxine-binding globulin (TBG) by the radioligand binding assay. The serum TSH and urinary T3 and T4 responses to 100 mug intravenous TRH were studied in five subjects during summer and again during winter. The serum concentration of these hormones and TBG did not reveal significant variations throughout the year. However, the mean urinary excretion of both T3 and T4 during coldest months (January and February), at 0.97 and 1.95 mug/24 hr, respectively were significantly higher than the corresponding values (T3, 0.48; T4, 1.18 mug/24 hr) during the hottest months (May-July). The TSH, and urinary T3 and T4 responses to identical doses of TRH during summer and winter did not differ significantly. Since urinary T3 and T4 indirectly reflect the prevailing unbound serum levels of these hormones, it is likely that the greater availability of free and biologically active thyroid hormones could help the body to adapt to cold by increasing nonshivering thermogenesis.