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The years since 2000 have been a golden age in in situ ocean observing with the proliferation and organization of autonomous platforms such as surface drogued buoys and subsurface Argo profiling floats augmenting ship-based observations. Global time series of mean sea surface temperature and ocean heat content are routinely calculated based on data from these platforms, enhancing our understanding of the ocean’s role in Earth’s climate system. Individual measurements of meteorological, sea surface, and subsurface variables directly improve our understanding of the Earth system, weather forecasting, and climate projections. They also provide the data necessary for validating and calibrating satellite observations. Maintaining this ocean observing system has been a technological, logistical, and funding challenge. The global COVID-19 pandemic, which took hold in 2020, added strain to the maintenance of the observing system. A survey of the contributing components of the observing system illustrates the impacts of the pandemic from January 2020 through December 2021. The pandemic did not reduce the short-term geographic coverage (days to months) capabilities mainly due to the continuation of autonomous platform observations. In contrast, the pandemic caused critical loss to longer-term (years to decades) observations, greatly impairing the monitoring of such crucial variables as ocean carbon and the state of the deep ocean. So, while the observing system has held under the stress of the pandemic, work must be done to restore the interrupted replenishment of the autonomous components and plan for more resilient methods to support components of the system that rely on cruise-based measurements.

Melonine is a basic monoterpene indole alkaloid (MIA) skeleton from Melodinus philliraeoides that was reported in 1983. The scarcity of its spectroscopic data questioned the validity of its structure. This prompted us to reisolate this molecule and to revise its structure into an unprecedented MIA scaffold. DFT-validated biosynthetic paths to both this new core and the originally reported form are proposed. The pathway to the original structure of melonine seems to be thermodynamically feasible, and that compound may exist as a natural product.

The ocean observing system needs to be ensured by high-level integration and coordination to guarantee its longterm sustainability, efficient accessibility and usability by a wide range of users. Enormous advancements and efforts toward these objectives have been already conducted in Europe, partly through the activities of the IOC-UNESCO's International Oceanographic Data and Information Exchange (IODE) and EuroGOOS DATAMEQ working group, although there is still room for additional progress and gaps to be addressed. During the past two decades, a series of standards for data and metadata formats as well as exchange protocols have been established within the marine community where projects, organizations and data integrators like JCOMM, RDA (Research Data Alliance), EuroGOOS, EMODnet, SeaDataNet and Copernicus played a significant role. Taking into consideration that harmonized data are a key element in maintaining a usable and interoperable ocean observing system, this paper aims to provide some recommendations for the harmonization of the marine in situ networks involved in EuroSEA, which would be a useful product for the European data integrators, particularly EMODnet, SeaDataNet and Copernicus Marine service. This document proposes recommendations to enhance the in situ networks based on the assessment of what has been previously done.

A review of the existing reporting tools about Regional Ocean Observing Systems and perspective toward future European Ocean Observing System monitoring and reporting services.

The Odyssey Project coordinated by OceanOPS, joint center of the World Meteorological Organization and the Intergovernmental Oceanographic Commission of UNESCO, will support and involve civil society, including citizens, sailors, businesses, etc., in observing the ocean and the atmosphere above it to contribute to the Global Ocean Observing System (GOOS) implementation.As the global population is set to reach more than 9 billion people by 2050, impacts on the ocean associated with human activities will escalate. Understanding the variability and trends of the ocean and the related impacts on our society, through sustained oceanographic and marine meteorological observations and ocean science, is essential to predict the consequences of change, guide mitigation, and design adaptation for the benefit of the nature and humankind.The Odyssey project embodies the level of response we need to face climate issues and will help strengthen collaborations within and outside the global ocean observing community. These collaborations, based on the met-ocean observations' collection, data sharing and analyses, scientific and technological developments, will be essential to develop such a project.

International audience; We report the enantioselective total syntheses of mavacurans alkaloids, (+)-taberdivarine H, (+)-16-hydoxymethylpleiocarpamine, (+)-16-epi-pleiocarpamine, and their postulated biosynthetic precursor 16-formyl-pleiocarpamine. This family of monoterpene indole alkaloids is a target of choice since some of its members are subunits of intricate bisindole alkaloids such as bipleiophylline. Inspired by the biosynthetic hypothesis, we explored an oxidative coupling approach from the geissoschizine framework to form the N1-C16 bond. Quaternization of the aliphatic nitrogen was key to achieve the oxidative coupling induced by KHMDS/I2 since it hides the nucleophilicity of the aliphatic nitrogen and locks the required cis conformation. Scheme 3. Synthesis of 16-deformyl-geissoschizine (22), geissoschizine (1) and geissoschizine malonate 23 according to our previous work. With a straightforward access to the geissoschizine framework, we were in position to evaluate our hypothesis of oxidative cyclization after quaternization of the aliphatic nitrogen N4. As

Context. Camellimidazoles A–C were recently reported as new natural substances arising from what was described as new caffeine degradation pathway in Keemun black tea. - Discoveries. Under alkaline hydrolysis conditions followed by spontaneous cascade reactions with formaldehyde or dichloromethane (as the key methylene group providers), we were able to achieve the synthesis of camellimidazoles B and C. A MetWork-based pipeline was also implemented highlighting a wealth of structurally diverse compounds formed in the course of the reaction and streamlining the isolation of the newly described camellimidazoles D-F, subsequently confirmed as anticipated in silico upon extensive spectroscopic analyses. Besides demonstrating the artefactual origin of camellimidazoles, the current investigation emphasizes the fitness of MetWork-tagging to illuminate the chemical diversity associated with seemingly simple reactive conditions.- Methods. Organic synthesis, phytochemical analysis, in silico anticipation, molecular networking dereplication

Bipleiophylline is a highly complex monoterpene indole alkaloid composed of two pleiocarpamine units anchored on an aromatic spacer platform. The synthesis of bipleiophylline is considered as a mountain to climb by the organic chemistry community. Here, a unified oxidative coupling protocol between indole derivatives and 2,3-dihydroxybenzoic acid, mediated by silver oxide, has been developed to produce the core of bipleiophylline. This method also allows the independent preparation of benzofuro[2,3-b]indolenine and isochromano[3,4-b]indolenine scaffolds, depending only on the nature of the aromatic platform used. The procedure has been applied to simple indole derivatives and to more challenging monoterpene indole alkaloids, thereby furnishing natural-product-like structures. The use of scarce pleiocarpamine as the starting indole allows the first syntheses of bipleiophylline and of its biosynthetic precursor, voacalgine A. The structure of the latter has been reassigned in the course of our investigations by 2D NMR and displays an isochromano[3,4-b]indolenine motif instead of a benzofuro[2,3-b]indolenine.