Publications by authors named "Vijay Kumar B"

A full account on the first total synthesis of a chroman meroterpenoid, (-)-phomoarcherin C, has been described. Key synthetic transformations include phenyl boronic acid-mediated 6π-electrocyclization reaction, a stereospecific hydrogenation driven by thermodynamic conformational stability of the product, and regioselective formylation. The strategy employed is considerably short, is atom-economical, and can open the doors to provide access to various other natural products of the same kind.

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The first biomimetic total syntheses of chromane meroterpenoids, guadials B and C, guapsidial A and psiguajadial D have been completed. The key synthetic transformation involves an efficient and high yielding hetero-Diels-Alder reaction. The two structurally isomeric natural products, guadials B and C, were obtained from a common o-quinone methide in the separate reactions with α-pinene and β-pinene, respectively.

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A simple, highly diastereoselective, Lewis acid catalyzed Friedel-Crafts coupling of a cyclic allylic alcohol with resorcinol derivatives has been developed. The method was applied for the enantiospecific total syntheses of structurally diverse natural products such as machaeriol-D, Δ(8)-THC, Δ(9)-THC, epi-perrottetinene and their analogues. Synthesis of both natural products and their enantiomers has been achieved with high atom economy, in a protecting group free manner and in less than 6 steps, the longest linear sequence, in a very good overall yield starting from R-(+) and S-(-)-limonene.

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Introduction: Sex chromatin is a plano-convex to triangular DNA mass measuring approximately 1μm in size and lying adjacent to the inner side of nuclear membrane in the somatic cells of the females. There is consistent loss in the sex chromatin percentage in the carcinoma cases in comparison to benign lesions and normal individuals.

Aim: To know the correlation between the sex chromatin status in female breast tumors on paraffin sections, buccal smears and peripheral blood films.

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Bacterial culture of semen samples from 100 male partners in infertile couples revealed the presence of aerobic bacteria in 49 cases. Streptococcus faecalis (Enterococcus) was isolated from 53%, micrococci species from 20% and alpha-haemolytic streptococci from 16% of the infected samples. The incidence of oligozoospermia and teratozoospermia was significantly (P < 0.

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Ten confirmed cases of invasive aspergillosis (IA) in cancer patients were analysed retrospectively. Eight were pulmonary, one was sinonasal and one was cutaneous. The majority of patients had haematological malignancies (7), the remaining three were cases of solid tumours.

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