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Herein we describe an unprecedented formation of a cyclopropane ring through the conversion of a methyl group that was not functionalized for the purpose. In a one-step reaction, 7-deacetoxy-7α-hydroxygedunin (4) afforded two new gedunin derivatives, namely 7-deacetoxy-13,14,18-cyclopropyl-7α,15β, 17ξ-trihydroxy-gedu-16-oic acid (7) and 7-deacetoxy-9,11-en-7α,15β-dihydroxygedunin (8) along with the known 7-deacetoxy-7,9-diene-15β-hydroxygedunin (5).

Ethnopharmacological significance Nigerian herbalists possess indigenous ethnomedicinal recipes for the management of tuberculosis and related ailments. A collaborative preliminary modern scientific evaluation of the efficacy of some Nigerian ethnomedicines used by traditional medicine practitioners (TMPs) in the management of tuberculosis and related ailments has been carried out. Materials and methods Ethnomedicinal recipes (ETMs) were collected from TMPs from locations in various ecological zones of Nigeria under a collaborative understanding. The aqueous methanolic extracts of the ETMs were screened against Mycobacterium bovis , BCG and Mycobacterium tuberculosis strain H 37 Rv using the broth microdilution method. Results Extracts of ETMs screened against BCG showed 69% activity against the organism. The activities varied from weak, ≤2500 µg/mL to highly active, 33 µg/mL 64% of the extracts were active against Mycobacterium tuberculosis The activities of the extracts against Mycobacterium tuberculosis varied from weak, ≤ 2500 µg/mL to highly active, 128 µg/mL. There was 77% agreement in results obtained using BCG or Mycobacterium tuberculosis as test organisms. Conclusion The results show clear evidence for the efficacy of the majority of indigenous Nigerian herbal recipes in the ethnomedicinal management of tuberculosis and related ailments. BCG may be effectively used, to a great extent, as the organism for screening for potential anti- Mycobacterium tuberculosis agents. A set of prioritization criteria for the selection of plants for initial further studies for the purpose of antituberculosis drug discovery research is proposed.

Most inflammatory agents activate nuclear factor-kappaB (NF-kappaB), resulting in induction of genes coding for cytokines, chemokines, and enzymes involved in amplification and perpetuation of inflammation. Hypoestoxide (a bicyclo [9,3,1] pentadecane) is a diterpene from Hypoestes rosea, a tropical shrub in the family Acanthacea, several members of which are used in folk medicine in Nigeria. Here, we demonstrate that hypoestoxide (HE) abrogates the production of pro-inflammatory cytokines (IL-1beta, IL-6, and TNF-alpha) in lipopolysaccharide (LPS)-activated normal human peripheral blood mononuclear cells. Moreover, HE inhibits the production of nitric oxide (NO) by IL-1beta- or IL-17-stimulated normal human chondrocytes. In vivo, oral administration of HE to mice significantly ameliorated hind paw edema induced by antibodies to type II collagen plus LPS. Furthermore, topical administration of HE to mice also significantly inhibited phorbol ester-induced ear inflammation. The anti-inflammatory activity of HE may be due in part to its ability to inhibit NF-kappaB activation through direct inhibition of IkappaB kinase (IKK) activity. Thus, HE could be useful in treating various inflammatory diseases and may represent a prototype of a novel class of IKK inhibitors.

Background: Niprisan is a new drug extracted from indigenous herbs that has been developed by the Nigerian National Institute for Pharmaceutical Research and Development for the prophylactic management of patients with sickle cell disease. Objective: The objective of this study was to assess the efficacy and tolerability of niprisan in the management of patients with sickle cell disease. Methods: This was a randomized, double-blind, placebo-controlled, crossover trial. Patients who met the criteria for homozygous sickle cell disease and had 3 painful or vaso-occlusive crises per year were randomized to 1 of 2 study groups. Group A took niprisan 12 mg/kg body weight for 6 months before crossing over to placebo for another 6 months; group B took placebo for 6 months before crossing over to niprisan for another 6 months. There was a 1-month washout period before the crossover. The main outcome measures were the incidence of crises; the occurrence of painful episodes; certain clinical, hematologic, and biochemical measures; and patients' daily self-assessment of health. Results: Eighty-four patients met the inclusion criteria, but complete data were available for only 69 patients at the end of 12 months, 33 in group A and 36 in group B. Loss to follow-up was related to social and logistic factors rather than study drug. One oral dose of 12 mg/kg niprisan daily significantly reduced the frequency of sickle cell crises, bone pain, and hospital admission ( P Conclusion: Niprisan was efficacious in the prophylactic management of patients with sickle cell disease, although additional confirmatory studies in larger sample sizes are needed.

The study was undertaken to determine the safety and efficacy of NIPRISAN, a phytomedicine, developed for the management of patients with Sickle Cell Disorder (SCD). The study design is a placebo-controlled double blind cross-over trial. Eighty-two (82) patients with SCD were recruited and randomised into two groups. An initial 4 month pre-trial study was undertaken to determine the similarity of the groups. The main study was conducted over a twelve-month period with crossover at six months. Safety of the drug was assessed clinically and biochemically. NIPRISAN significantly (P < 0.01) reduced the frequency of SCD crisis associated with severe pains. Acute toxicity to the liver assessed by the activities of liver enzymes, indicate that NIPRISAN is safe. Renal function assessed by the serum levels of creatinine and blood urea nitrogen remained normal. Both the clinical and laboratory results of the present phase IIB (pivot) clinical study suggest that NIPRISAN is a safe and efficacious phytomedicine for the management of patients with Sickle Cell Disorder.

Summary Effects of 3, 5 - dimethoxy - 4 - hydroxybenzoic acid and 2, 3, 4 - trihydroxyacetophenone were studied on haemoglobin S (Hb S) polymerisation, analgesia and inflammation using Hb S solution, rats and mice. UV spectrophotometric procedure was used to monitor the polymerization of the Hb S. Acetic acid induced writhing in mice and egg albumin induced rat paw edema procedures were used to evaluate analgesic and anti-inflammatory activities of the compounds respectively. The results indicate that both drugs inhibit the process of polymerization significantly, possibly by direct action on the Hb S molecules. The drugs inhibited acetic acid induced pain and decreased egg albumin induced oedema. It is concluded that 3, 5 - dimethoxy - 4 - hydroxybenzoic acid and 2, 3, 4 - trihydroxyacetophenone may have some value in the management of sickle cell disease.

This study examines the anthelmintic activity of a methanol, hexane and ethylacetate extracts of Berlina grandiflora and purified betulinic acid, the major triterpenoid found in the extract. Caenorhabditis elegans, a free living soil nematode was used as in vitro model in the study. A suspension of worms was treated with the extracts. After seven days of incubation activity was assessed in terms of number of worms exhibiting motiliy. The results showed that methanol, hexane and ethylacetate fractions at 500 ppm showed anthelmintic activities in the order ethylacetate > methanol > hexane from the alcoholic crude extract. The isolated betulinic acid from the ethylacetate fraction at 100 and 500 ppm showed strong anthelmintic activities comparable to piperazine. These results confirm the traditional use of Berlina grandiflora as an anthelmintic and indicate that betulinic acid is the active component.

The production of citric acid from imumu Cyperus esculentus and maize Zea mays was carried out using Aspergillus niger . Hydrolysis of the substrates at 97°C produced a higher concentration of reducing sugars than at 40°C. The concentrations of citric acid were higher in unagitated and defatted cultures compared to agitated and undefatted cultures respectively.

During the determination of the constitution of ekersenin isolated from Ekererbegia senegalensis , eight isomeric monomethoxy-monomethylcoumarins were synthesised. These studies proved that ekersenin was 4-methoxy-5-methylcoumarin, a constitution with novel biosynthetic implications. Apparently ekersenin is the first example of natural coumarin biosynthesis involving only the polyketide route. Comparative spectral correlations on substituted coumarins are summarised.

Crude-oil samples from three oilfields in the east and west of the Tertiary Niger delta, Nigeria, were analysed for pentacyclic triterpanes by gas chromatography and gas chromatography—mass spectrometry. Previously identified pentacyclanes such as 18αH-oleanane; 1(10→5)-abeo-3β-methyl-24β-nor-25α-18αH-oleanane (spirotriterpane); 30-nor-17αH,21βH-hopane; 17αH,21βH-hopane and 22,29,30-trisnor-18αH-hopane-II were recognised in the crudes. In addition, 17βH,21αH-hopane (moretane) and 17βH,21αH-homohopane (homomoretane) were identified for the first time. Results obtained in the present study indicate that the Nigerian petroleum pentacyclanes belong to at least three homologous series, namely, the 17αH,-21βH-hopanes (αβ); 17βH,21αH-hopanes (βα) and a novel “ K 1 ” series distinguished by members with retention times that were considerably shorter than those of the corresponding αβ hopanes with the same number of C atoms. Mass-spectral and retention-time characteristics of the “ K 1 ” triterpanes classified them neither as the 17αH-hopanes (αα hopane series) nor the recently-discovered methylhopane series. The preponderant pentacyclic triterpanes in the oils sampled from either side of the delta were the αβ hopanes and oleananes. However, the triterpane fingerprint of the western crudes differed significantly from that of their eastern counterparts in the distribution of the oleananes. The relatively higher concentration of the oleananes in the eastern oils apparently reflects a greater input of higher plants to their source sediments, presumably the shale of the paralic Agbada Formation. The relatively lower concentration of the oleananes in the western oils resulted in a dominantly hopane fingerprint, expected for petroleum generated in mainly non-terrigenous source rocks. Therefore, it would appear that the concentration of oleananes in Nigerian petroleum is sufficiently variable with source facies to permit dependable oil—source rock correlation based on triterpane finger-printing.

The structures of piperolein acids guineensine and wisanine have been confirmed by synthesis, UV irradiation of trans piperolein B acid ester gave the cis-isomer reported in the literature as the trans-isomer. The trans-2, trans-4 ethylenic bonds in guineensine and wisanine were introduced by reacting piperolein B aldehyde and 2-methoxy piperonal with the appropriate Wittig or Reformatsky reagent.

Immature shale of the Agbada Formation of the Tertiary Niger delta, Nigeria, cored at various depths A simulation experiment carried out by heating the immature shale at 300°C in vacuo (0.4 Torr) for ten days resulted in a triterpane composition similar to that of the delta oils. The disappearance of olean-13 (18)-ene and the generation of oleananes had apparently occurred simultaneously with reported structural changes in the hopane components. The presence of the triterpene in immature shale and its apparent transformation to 18αH-oleanane by in vitro thermal alteration was consistent with the current hypothesis of the origin of oleananes in Nigerian petroleum.

Ekweozor, CM., Okogun, J.I., Ekong, D.E.U. and Maxwell, J.R., 1981. C 24 –C 27 degraded triterpanes in Nigerian petroleum: Novel molecular markers of source/input or organic maturation? In: A.W. Rose and H. Gundlach (Editors), Geochemical Exploration 1980. J. Geochem. Explor., 15: 653–662. The analyses, by gas chromatography and gas chromatography/mass spectrometry, of the triterpane concentrate of crude oils sampled from various oil fields of the Tertiary Niger delta have revealed the ubiquitous presence of a series of C 24 –C 27 tetracyclic alkanes likely to be novel degraded triterpanes. The presence in the crude oils of a C 25 tricyclic alkane, apparently structurally related to the tetracyclanes, seemed consistent with the hypothesis of sequential cleavages of the terminal rings of precursor pentacyclic triterpenoid derivatives with increasing thermal transformation of the respective petroleums. The degraded triterpanes might be useful for assessing the stages of thermal evolution of petroleum in the reservoir. A possible application, to oil exploration, of the expected variations in the concentration of the polycyclanes in crude oils with different thermal histories would be in distinguishing primary (immature) oils from mature but bio degraded oils.

Summary A comparative study of some of the hormones in acidic extracts obtained from fruits of cowpea was undertaken in relation to premature fruit abscission. Extracts were obtained from 6-day and 2-day old fruits from the lowest and upper racemes of the cowpea inflorescence, respectively. In the cultivar New Era, only growth inhibitors were detected in 2-day old fruits whereas inhibitors as well as gibberellins and auxins were detected in 6-day old fruits. In the cultivar Adzuki, gibberellin activity was detected in both 2-day old and 6-day old fruits. The results are discussed in relation to the abscission problem in cowpea.

Arjunolic acid and a new triterpene acid, myrianthic acid, were isolated from the rootwood of Myrianthus arboreus . The structures of the two compounds were elucidated by IR, 1 H NMR and mass spectroscopy.

Abscisic acid, phaseic acid and 4′-dihydrophaseic acid were identified by GC-MS of derivatized (Me, MeTMSi) extracts from immature fruits of Vigna unguiculata. The fruits also contained some other ABA-related compounds, one of which might be epi-4′-dihydrophaseic acid while another was tentatively identified as 6′-hydroxymethylabscisic acid.

X-substituded benzamides (X = H; 2-OH; 4-MeO; 3-MeO; 3,5-(MeO) 2 ; 4-Cl and 2,4-Cl 2 ) have been shown to add reversibly to the dienyl rings of the organometallic compounds [(dienyl)Fe(CO) 3 ]BF 4 (dienyl = C 6 H 7 , 2-MeOC 6 H 6 or C 7 H 9 ) to give the corresponding cationic tricarbonyl(substituted-diene)iron complexes.

A tricyclic diterpene ketone, roseadione, has been isolated from Hypoestes rosea and its structure established as a dicyclopenta[ a , d ]cyclo

The hydrocarbon constituents of the leaf waxes of eight species of Khaya were analysed for taxonomic purposes using GLC. The leaf waxes contained neither isoalkanes nor alkanes and the bulk of the n-alkanes were in the range of C25 to C33, odd-carbon number compounds predominating. It was found that the percentage composition of the n-alkane constituents of the leaf waxes varied with the age of leaves, young leaves having n-C29 as the most abundant alkane, whereas older leaves had n- C31.